Preheat oven to 350 degrees.

Make a thick béchamel sauce in a small saucepan by cooking the butter and flour together until they foam for 2 minutes without coloring. Off heat, beat in the boiling milk and seasonings. Boil, stirring, for 1 minute. Allow to cool while preparing other ingredients, beating occasionally.

Place the livers, eggs, egg yolks, and seasonings in the blender, cover, and blend at top speed for 1 minute. Add the cool béchamel sauce, cream, and wine to the liver and blend for 15 seconds. Strain through a sieve into a bowl. Stir in the optional truffle and correct seasoning. (If not used immediately, cover and refrigerate.)

Butter the interior of the ramekins or mold heavily. Pour in the liver mixture filling each ramekin or the mold to within about 1/8 inch of the top.

Set in pan of boiling water, then place on a rack in middle level of preheated oven for 25 to 30 minutes, until a needle or knife plunged into the center comes out clean, and the timbales have just begun to show a line of shrinkage from the ramekins. (If not served immediately, leave in hot turned-off oven, with door ajar, for 15 to 20 minutes.)

Run a knife around the edge of each timbale and reverse onto a serving platter or serving plates. Top each with a spoonful of sauce, and pass the rest of the sauce separately.

VARIATIONS

Using the same proportions and method, substitute for the chicken livers any of the following cooked ingredients: ham, chicken, turkey, sweetbreads, salmon, lobster, crab, scallops, mushrooms, asparagus tips, or spinach.