To 1litre (1¾pt or 4½U.S. cups) Crème d’Ecrevisses add 1litre (1¾pt or 4½U.S. cups) Crème d’Eperlans, both soups being completely finished with cream only (see Velouté d’Ecrevisses and Velouté d’Eperlans). Stir together gently but without completely mixing them.
1tbs small Quenelles made from smelt and cream forcemeat to the size of peas; 1tbs pea-size balls of very black truffle; 1tbs cooked crayfish tails cut in small dice.