Sauce Génoise (Cold Pistachio and Herb Sauce for Fish)

Ingredients

• 40 grammes pistachios
• 25 grammes pine nuts
• A small spoonful cold Sauce Béchamel
• 6 egg yolks
• A pinch of fine salt
• A dash of pepper
• 1 litre oil
• Juice of 2 medium lemons
• 3 spoonfuls herb purée made from parsley leaves

Instructions

1. Grind 40 grammes of pistachios and 25 grammes of pine nuts — or sweet almonds failing those — in a mortar to a fine, smooth paste, adding the equivalent of a small spoonful of cold Sauce Béchamel.
2. Pass the paste through a fine sieve and put it in a terrine.
3. Add 6 egg yolks, a pinch of fine salt and a dash of pepper, and mix well with the whisk.
4. Mount the sauce with 1 litre of oil and the juice of 2 medium lemons.
5. For the herb purée: take parsley leaves, chervil pluches, tarragon, chives and young burnet in season in equal quantities, blanch them briskly for 2 minutes, drain, refresh, press strongly, and pass through a fine sieve.
6. Complete the sauce with 3 spoonfuls of this herb purée.
7. Serve with cold fish.