Leek Stuffed with Chicken Mouse, Garlic Cream Espuma (not successful)

This was an experiment which was not successful, for a variety of reasons. It tasted fine enough, but the textures and shapes were all wrong. It's a learning experience and provides clues to things we can improve.

The idea was to take a leek (ha!), pull out the individual cylinders, stuff them with a chicken mousse, and cook both to soften the leek and set the mouse. I wanted a hot foam of whip cream with a garlic flavor on top. It was based on two dishes we'd done before: Cannelloni of Chicken Mousse (2007) and Bacalao Espuma. 

The Espuma is pretty nerdy and requires some unusual gear. I'll give the ingredients and procedure, then discuss what went wrong, and some ideas for future experiments.

Leeks, Espuma, red peppers, zuchinni

Garlic Cream Espuma

 100 ml    Cream (35% fat)

   4 clove Garlic

   1 g     Agar Agar (powder from Tienda Parami)

  30 ml    Water

Leek and Chicken Mousse

   1 large  Leek

 230 g      Chicken Breast

  35 ml     Cream (35% fat)

  70 g      Egg White

0.75 g      Salt

Use a garlic press or mince the Garlic and add to the Cream.

Simmer very low for 30 minutes; we want to extract the flavor.

Hydrate the Agar Agar in Water and whiz to disburse.

Add to the Garlic Cream and bring to bubbling simmer for 5 minutes to fully dissolve the Agar Agar.

Whiz to disburse the Agar gel in the cream.

Chill until it gels.

Whiz the gel to create a "fluid gel" and return to heat at 65C / 150F; don't go too high because it will denature the fluid gel.

Load into an iSi Whipper and charge with two N2O cylinders.

Hold in water bath at 65C / 150F serving temperature

Cut the root and dark green end from the Leek. Separate the cylindrical layers -- this turned out to be much more difficult than I expected. Keep the good cylinders for stuffing, reserve the rest for something else.

Whiz the Chicken Breast in a food processor or blender until pretty smooth, without heating so you don't cook it. Add the Cream, Egg White, and Salt, and process a bit more until as smooth as you can get.

Fill a pastry bag with the Chicken Mousse and then stuff the Leek cylinders: you'll probably have to fill from both ends if you have a long leek.

Steam for 45 minutes.

Remove the cooked Leeks and Chicken, and plate.

Invert the iSi and dispense the Garlic Espuma on top.

Serve.

What went wrong

The Egg Whites in the Chicken Mouse caused them to expand and blow out the Leeks.

The Leeks split along their fiber lines. In retrospect: totally obvious. They're tough fibers across the grain but with the grain they tear easily.

The texture of the Chicken was not mousse-y enough, it was rubbery: too much Egg White and perhaps overcooked.

The Chicken Breast was mono-dimensional in flavor. 

The fluid gel set up well but never returned to a ketchup-like viscous liquid after whizzing. This thickness prevented the iSi from being able to express a foam.  The meager amount may not have been enough for the iSi vessel size anyway; the previous Bacalao Espuma used a larger volume. The two person serving size was probably too small to be workable in the iSi.

Future guidance

Leeks are a pain in the butt to separate: the inter-layer film grips strongly. I'm not sure what I could do to reduce the friction. Maybe I shouldn't use Leeks. What then? Restaurant Alinea (Chicago) fills Palm Hearts, but that's not as large as I was looking for.

Leeks will always split along their fibers: we can't have any filling which expands. Perhaps skip the Egg White and increase the Cream to ensure it's soft enough to pipe into the Leeks.

The Cannelloni Mousse we based this on used a mixture of light and dark meat as well as chicken liver to provide a rich flavor. Do that again, or just use dark meat chicken and liver.

The fluid gel needed to be fluid before going in the iSi. There are different strengths of Agar, even at the store I got this from, Parami. Perhaps this one was too strong, that others would be softer. Try halving the Agar. If you have different Agar, try gelling and whizzing and see if it creates a saucy texture. I think there are a lot of opportunities for warm/hot foams -- "espumas" -- with Cream so it might be worth spending a few bucks on Cream and N2O to find out what proportions work, before worrying about flavors.

Perhaps increase the amount of the Garlic Cream, even if we don't use it all, so the iSi Whipper has enough to work with.

Turbot with Creamy Leek Sauce a la Restaurant Le Jules Verne

My favorite dish at Restaurant Le Jules Verne (in the Eiffel Tower, Paris) was a Turbot with creamy leek sauce that was a bit fluffy: it was completely smooth and my photo hints it might have used an iSi whipper to get the light texture. It tasted distinctly of leeks and was topped by a couple charred stems of what looked like baby leeks which exuded a beckoning allium aroma. 

Merluza with Leek Sauce, charred Garlic shoots; served with Mashed Potatoes

I'm trying to reverse-enginerr this and expect it will take a few tries. This turned out pretty well, a tasty dish, good enough to serve to friends, but not an accurate recreation. It's worth trying again with some minor tweaks, but -- happily -- the sauce texture was rather good without resorting to an iSi and hydrocolloids; to pursue nerdiness for finesse and fluff, see below the recipe for leads.

Jules Verne had more green, finesse; and no side dish

I'm starting with proportions from Martha Stewart (who discards half of her batch and uses chicken stock), Charlotte Puckette (whose recipe is straight forward, adding parsley perhaps for color), and Food.com (which adds Lemon Juice instead of wine). 

David Lebovitz says to cook the leeks long and slow in butter with a bit of oil to prevent the butter from browning, and the comments say that letting them brown brings out bitter tastes. The Guardian (and others) says not to waste the green part as it has more flavor but should be cooked longer; it also suggests slicing the dark green parts thinly and then frying until crispy which seems like a good garnish.

For 2 portions:

250 g   1 giant  Leek, white to light green, cut in thin rings

 30 g       2 T  Butter

 15 ml      1 T  Olive Oil

 pinch           Salt

 60 ml    1/4 C  Dry White Wine

120 ml    1/2 C  Heavy Cream

  ?              Lime Juice (half of one lime, not all used)

  2 whole        Garlic Shoots [these have a Catalan name]

340 g            Turbot steaks (I used Merluza because I had it)

                 Olive Oil

Trim Leek root and ragged ends.

Slice from white part to green to quarter but leave bulb end intact; wash any sand, then slice thinly crosswise.

Sautée Leeks in Butter and Oil on low heat, covered, stirring occasionally, until quite soft, about 20 minutes. 

Add Wine, increase heat, and reduce until evaporated.

Add Cream and simmer 5 minutes.

Transfer to blender and whiz until it won't get any smoother.

I had to add another 90 ml Wine because it was too thick to blend well.

The result was fairly fluffy -- not as airy as Jules Verne's, but good enough for serving.

Strain through a medium sieve: I had 350 g before, 290 g after sieving.

Trim the Garlic Shoots, slice carefully lengthwise, and cook on a heavy pan to brown. Use a filim of oil since we're trying to char and crisp, not sautée. Cover and weigh down; I used a chunk of granite kitchen counter top sample. Cook on medium, carefully turning to brown both sides. Try and brown the stems too.

The restaurant menu said "cuit au naturel", which we believe translates as steam or poach. My interpretation is they don't want to give the fish any color or flavor from browning you'd get from a sautée.

This didn't occur to me, this time, so I filmed a pan with Olive Oil, and cooked the Merluza (Hake) fairly slowly, covered, to avoid browning. Season with Salt and flip when about half done. Flip once more and check the fish to see if it flakes readily.

While the fish cooks, heat the Leek Sauce; if it sags, fluff with a whisk.

To serve, put a layer of sauce on the plate, add the fish, and top with more sauce.

Garnish with the browed Garlic Shoots.

Served with golden mashed potatoes, too similar in color.

Tasting

This is good, but not leek-y enough. And not green enough. Not what I was aiming for -- a faithful rendition of a Michelin-starred restaurant dish --  but I'd be happy to serve this to friends, even fancy foodie friends. I'd like more leek-taste and Irene wanted less butter.

The Merluza/Hake had a good texture, large firm flakes when cooked gently to 57C/135F or a bit above.

Next time...

Use one 150g Leek, not a 250g behemouth. 

Use dark green leek bits to get more flavor and the deeper color that Jules Verne had. 

Blanch and shock the green parts first so they don't turn grey when cooking.

Less butter: there was plenty for the 250g leek, so cut the butter at least in half.

Since I had to add Wine to thin it enough to blend, why add the Wine to the pan and reduce it away? Instead, add to blender, then cook off after blended and strained, so we can get the saucy texture we want.

Use Turbot, since that's what Jules Verne used. Or not: the Merluza/Hake was good for this -- firm with large flakes.

Cook the fish sous vide from frozen ("naturale" on the menu suggests steamed or poached).

Fry some green leek rings, or rings from the garlic shoots.

When charring the garlic shoots, use a minuscule film of oil: we want the char.

There was no color contrast when served with mashed potatoes. There wasn't much contrast between the Merluza and the Leek Sauce either. Try and get a more intensely green sauce. Serve a side dish of a very different color: arroz negro, sepia ink pasta,...,  something more dramatic. Or use Salmon for the fish: we don't have to use Turbot or anything similar.

To get a really fluffy/airy texture, try the iSi Whipper with Agar Agar fluid gel. It'll be a lot more work but it's "'playing with your food". 

iSi Whipper for Fluffy "Espuma"

TL;DR: after reading the below, I'd try the following:

After the first medium sieve,  I'd run it through a fine sieve to prevent clogging the iSi. Then add back to the pan, add 0.6-1.0% by weight of Agar, bring to simmer for 5 minutes, then chill until gelled. Whiz to make a fluid gel, heat to serving temperature, 65C/150F, then put in the iSi. Charge with an N2O cylinder and hold at serving temperature in a water bath.

Below are links to techniques and materials:

How can I use an iSi whipper to make a hot foamy sauce, an "espuma"? In my research for Bacalao Espuma, I found Xanthan and Agar Agar didn't gel well, and ended up using potato for the starch.

Cuisine Technology points out "milk holds bubbles better while hot, and cream does better when it’s cold", and "starches is that they work in either hot or cold" but we want to avoid it getting too thick. Also "Lecithin works (and dissolves) in both hot and cold water", and that Agar, once set, will stabilize up to 185F/85C so fine for a hot foam, but the procedure is a bit complicated in that you have to make a "fluid gel".

Amazing Food Made Easy talks about fluid gel foams, amongst others. 

There are pointers to lots of inventive preparations on Molecular Recipes. This one for an clam chowder espuma doesn't use anything to bolster the cream before going into an iSi whipper -- like I used in this first attempt for leek cream sauce. 

Bacalao Espuma

Scandinavia produces a lot of salt cod -- Tørfisk, Klippfisk, Clipfish. They can dry it in the cold air without worrying about spoilage. I first had it in Spain, as Bacalao, and fell in love with the slightly funky flavor it contributes to dishes.

For a Scandinavian dinner, I wanted a stable warm foam, or "espuma", to top a birch-wrapped, sous vide cooked cod fillet. I wanted to double-down on the cod.

From previous attempts, I've found it hard to keep a foam stable at high temperatures: whipped cream preparations are typically served cold. My additions of Agar Agar and even Xanthan Gum (in small amounts) didn't help much. I was looking for something almost as thick and solid as whipped cream, or at least shaving foam.  Ferran Adriá refers to these warm temperature foams as Espumas so I will follow suit.

Here, I synthesize what I hope is a simple but stable Bacalao-flavored espuma. This is a condiment so I don't need a ton; I'm targetting a 1.0L iSi Thermo Whip so a maximum of about 0.5L product.

To top 6 filets

• 250     g       Bacalo, bone- and skinless, rehydrated and desalted
• 250     g       Potato, peeled
• 250     ml      Heavy Cream

Rehydrate the Bacalao and soak in water for 2-3 days, changing the water 2-3 times a day to remove much of the preservative salt.  Cut it up fine so it will stay submerged in the Cream.

Simmer the Bacalao very low in Heavy Cream to infuse flavor, 30-60 minutes. You don't want it to bubble and reduce. (A sous vide bath might be helpful for this).  [I might need more Cream to Bacalao]

Meanwhile peel potato and cube, and boil 20 minutes until just cooked.  (Can I just cook the potato in the cream for 20 minutes?)

Thoroughly blend cooked potatoes and Bacalao cream, preferably in a Vitamix. While it whipped, it did NOT create a whipped cream: this was in retrospect a bit of a surprise; why not? Does this bode ill for the espuma?

Strain through coarse then very fine mesh seive. This gave me 400ml of bacalao-potato-cream.

Pour into iSi Thermomix. Check your volume, it should not be more than half full.  Charge with 2 N2O cream cylinders and shake vigorously. Hold in a water bath at a max of 75C (165F) until ready for service.

Resources

Below, I cite a number of recipes and resources from around the web. Some use additional flavors (shallots, coconut cream, chicken stock, cheese) but I wanted to let the Bacalao flavor dominate. The techniques I kept finding seemed to use heavy cream and potato: the fat from the cream will foam, and the starch in the potato may provide some stabilization.

iSi Potato Celeriac Foam (75C)

http://www.isi.com/en/culinary/for-professionals/recipes/recipes/recipe-of-the-month/?tx_isirecipes_recipes%5Brecipe%5D=1372&tx_isirecipes_recipes%5Baction%5D=show&tx_isirecipes_recipes%5Bcontroller%5D=Recipe

150 g Potatoes (floury)
75 ml heavy cream
75 ml Water
50 g Butter
75 g pureed celeriac
1 g Salt
1 g Pepper
1 g Nutmeg

Bring the cream and water to a boil in a pot and then, along with the boiled potatoes, blend into a fine puree. Add the pureed celeriac and the butter little by little then season to taste with salt, pepper and nutmeg. Pass through the iSi funnel & sieve directly into the 0.5 L iSi Whipper, screw on 1 iSi cream charger and shake vigorously. Keep the iSi Whipper warm at max. 75 °C in a bain-marie or in a water bath.

Espuma caliente de grasa de foie gras

http://vimeo.com/37517154
Xanthan 2.5g
Chick stock 300g
Whiz wiht immersion blenter very well
Add pepper, salt
Melt foie gras, add to Xanthan stock, whiz well
Striain, add to siphon
2 charges N2O
Hold at 70C

Potato Espuma

http://www.thestaffcanteen.com/recipe/potato-espuma/
600g cooked potatoes
450g hot double cream
150g hot milk
seasoning

Boil potatoes just until cooked, drain and slightly cool, peel and mash potatoes Add seasoning, add hot liquids and check seasoning adjust were needed, pass through double sieve, place into charger and use two charges and keep warm at 55oc

Pea Espuma (warm)

http://www.isi.com/en/culinary/for-professionals/recipes/recipes/vegetable-espumas/?tx_isirecipes_recipes%5Brecipe%5D=1104&tx_isirecipes_recipes%5Baction%5D=show&tx_isirecipes_recipes%5Bcontroller%5D=Recipe&cHash=635b0b38457dffc706c8fab2c5c212fc

200 ml heavy cream
100 g Peas
150 g Potatoes

Peel the Potatoes, cook until soft and mash with a potato masher. Blanch the Peas and puree in a blender until smooth. Heat the Heavy Cream, mix with the potatoes and the pea puree and season with salt, nutmeg and 50 ml mint oil. Pass through the iSi funnel & sieve directly into the 0.5 L iSi Whipper, screw on 1 iSi cream charger and shake vigorously. Keep the iSi Whipper warm at max. 75 °C · 165 °F in a bain-marie or in a water bath.

Potato foam 

250 g potatoes, peeled and cut into chunks
125 g single cream
30 g virgin olive oil, plus extra for drizzling

Place the potatoes in a pan of cold water, bring to the boil, and cook for about 20 minutes until soft. Drain, reserving 100 g of the cooking water. Place the cooked potato and the water in a blender. Purée, adding the cream little by little. Follow the same procedure with the oil until you have a smooth emulsion. Season with salt. Strain, then fill the siphon using a funnel.  Charge with nitrous oxide, shake, and keep warm in a bain-marie at 70 ºC.  Ferran Adria via http://www.chubbyhubby.net

elBulli Hot potato foam

http://www.foodsfromspain.com/icex/cda/controller/pageSGT/0,9459,35868_6908153_6910167_4459102,00.html
250 gr potatoes for mashing
100 gr potato cooking water
125 gr cream, 35% fat content
35 gr extra virgin olive oil
500 ml ISI siphon
2 N2O chargers
salt

Peel and cut the potatoes and place in cold, salted water. Bring to the boil and cook for approximately 20 minutes. When cooked, drain and reserve the water. Place the cooked potato and 100 g / 3 1/2 oz cooking water in the Thermomix at 60ºC / 140ºF. Blend and gradually pour in the cream. Do the same with the oil until a very thin, smooth emulsion is formed. Season with salt. Strain and fill the siphon using a funnel. Charge the siphon and place in a bain-marie at approx. 70ºC / 158ºF.