Langoustine Sauce

Ingredients

• langoustines (Norway lobsters)
• water
• white wine
• salt
• onion
• manteca (lard)
• flour
• 1 egg yolk, raw

Instructions

1. Cook the langoustines in water, white wine, salt, and onion until cooked through.
2. Allow to cool completely, then separate and shell the tails, reserving them.
3. Pound the bodies and shells in a mortar, dissolving them with the cooking liquid.
4. Pass everything through a fine sieve.
5. Heat the manteca until very hot and brown the flour in it, stirring to form a roux.
6. Mix in the strained cooking liquid and the raw egg yolk, stirring to incorporate.
7. Add the finely chopped langoustine tails and pour the finished sauce over the fish.