Served at Peterhouse, Cambridge, in the 1920s, this mousse is very good as a first course at dinner or as a cold luncheon dish. In the original recipe the mousse was surrounded by 24 mottled, dark-green gulls’ eggs, three for each serving, lying close and neatly around it on pale green lettuce. But gulls’ eggs are rarely obtainable and very expensive and the mousse is excellent in its own right.
Pound the fish with a wooden spoon in a large bowl. Stir in the cream, lemon juice, seasoning, tarragon and nutmeg. Fold in the egg whites
Turn the mousse out while still just warm and then chill for at least 1 hour.
Decorate with the olives and serve surrounded by the sprigs of watercress or lettuce, and with the mayonnaise.
©1980 The Estate of Elizabeth Ayrton