Mousse de Poisson — Cold Fish Mousse

Cold fish mousse is one of the poissonnier's most refined cold preparations — a velvet-smooth purée of raw or cooked fish, bound with velouté and gelatin, lightened with whipped cream, and set in a mould for unmoulding and presentation. It appears on cold buffets, as a first course, or as a component of more elaborate presentations (salmon mousse inside a paupiette, or lining a fish terrine). The classical method: purée 400g raw fish flesh (salmon for colour, sole for purity, pike for tradition) in a food processor until completely smooth. Push through a fine tamis twice — this removes every fibre and produces an almost liquid smoothness. Season firmly (the cold dulls flavour — season 20% more than tastes correct at room temperature). Prepare 200ml aspic or strong fish fumet with 8g leaf gelatin (bloom in cold water, dissolve in the warm fumet). Combine the fish purée with 150ml thick fish velouté and the gelatin-enriched fumet. Stir over ice until the mixture begins to thicken (approaching the setting point of 15-20°C). At this moment — not before, not after — fold in 200ml softly whipped cream (it should just hold its shape; over-whipped cream makes the mousse grainy). Pour into a lightly oiled mould (ring mould, dariole, or terrine), smooth the surface, and refrigerate for at least 4 hours or overnight. To unmould, briefly dip the base in warm water (5 seconds), invert onto the serving plate, and give a sharp downward shake. Decorate with cucumber slices, chervil, and a mirror of aspic. The mousse should slice cleanly, hold its shape on the plate, and melt on the tongue — the texture of a culinary cloud.

• Scandinavian fiskefars (fish farce for moulds)
• Japanese kamaboko (steamed fish paste — different texture, similar concept)