Wine-Cream Mousse with Champagne Sabayon

Mousse with Sponge Cake

Juice of 1/2 lemon
3/4 to 1 cup white wine
4 egg yolks
1/8 cup sugar
8 pieces gelatin leaves (or 2 packages gelatin), dissolved in 2 to 4 tablespoons warm water
1 quart heavy cream, whipped
1 sponge cake (or enough ladyfingers to line a large mold)
1 small bunch pink seedless grapes (or other grapes)

Combine juice, wine, yolks, and sugar. Heat in double boiler until foamy and stiff. Stir constantly with fine wire whip. Set aside to cool in bowl of ice water. When cold, add dissolved gelatin, then fold in whipped cream using a wooden spatula. Place 1/4-inch layer of cake on bottom and side of ceramic mold. Place a few seedless grapes over cake bottom, and fill mold with mousse. Cool in refrigerator for 1 hour.