Ajoarriero Aragonés: bacalao, potato, and egg -- cool and smooth

We had this at Tasca Angel in Valencia and it felt like comfort food for the dog days of summer: a cool mashed potato or brandade-like texture that was fine on its own or smeared on bread. This version from Aragon is different from the one with the same name from Navarra which is a stew that adds tomatoes and peppers. The recipe originated with mule drivers (arrieros) who could carry potatoes and dried salt cod on their overland journeys, and is very similar to "atascaburras" ("something that blocks a donkey's way") from Castilla-La Mancha.

Garnished with parsley, served with toast

Unsurprisingly, there are wide variations. Many recipes make this with chopped eggs, some with chunky potatoes; others add onion or bread crumbs.  In this video for "atascaburras o ajoarriero", Chef Teresa Carrascosa whips a LOT of olive oil into the cooked potatoes then mixes the shredded bacalao by hand. It's frequently garnished with quartered boiled eggs, walnuts, and/or parsley. 

Recipes range from 4:1 potatoes to bacalao to about 1:1 by weight; we'll start with 2:1. Here, I'm looking for a smooth texture and minimal ingredients.   I've got a potato ricer which makes a really smooth mash, but we can't pass bacalao through it; if you've got a potato masher, you can mash them both together.

Makes 600 ml, 555 g, and serves 4 as a hearty first course but you'll probably want some later.

A few simple ingredients

If needed, desalt the Bacalao in multiple changes of water for two days, or use ready-to-cook "al punt de sal" without hydrating.

200 g      Bacalao (desalted)

400 g      Potato (for baking, mashing, not waxy)

 75 ml     Olive Oil, Extra Virgin, good quality

  2 clove  Garlic, minced

  1        Egg, beaten

In a small pan, lightly sauté the Garlic in a small amount of the Oil to tame it for Irene, remove from heat after 5 minutes (normally it's added raw, mashed with a mortar).

In a medium pot, gently simmer the Bacalao in water 4-5 minutes until almost tender, remove, discard any skin and bones, then crumble or chop finely.

Bring the water back to a boil, slice the Potatoes 1/2 cm thick, and cook until barely done (maybe 15 minutes?)

Drain Potatoes, reserving some of the water.

Add the Garlic Oil to the now empty pot.

Pass Potato slices through a potato ricer into the pot with Garlic Oil. 

Add beaten Egg to the Potatoes and combine, ensuring they doesn't coagulate in one place.
Add the Bacalao and combine.
Drizzle in the rest of the Oil and mix to a smooth consistency like loose mashed potatoes; if it seems too thick, add a bit of the reserved water and more Oil.
Adjust Salt if needed but the Bacalao will probably bring enough of its own.
Allow to cool to room temperature then cover and cool.
Serve cold, cool, or room temperature, garnished with parsley; spread on bread or toast.

In cold weather, this could be served hot and warming like an intense potato purée.

How was it? Next time...

This turned out well, but not as smooth as at Tasca Angel -- I suspect they passed theirs through a tamis. 

I used the medium holes of the potato ricer and that let some skins through so use the smallest holes next time.

Irene said it needed more bacalao flavor so next time reduce the Potato to 300 g.