Get out you prettiest party glasses to fill with layers of coffee whipped cream and chocolate mocha mousse for this make-ahead dessert. Be sure to spread the layers neatly to the edges of each glass so the different colors show through. The truffle sauce must cool but still remain pourable before it is used. Warm truffle sauce would cause the whipped cream to deflate when the two are mixed.

In a medium saucepan, heat the 6 tablespoons cream and the butter over low heat until the cream is hot and the butter melts. The mixture should form tiny bubbles and measure about 175°F. on a thermometer; do not let the mixture boil, or it may form a skin on top. (If this does happen, use a spoon to carefully lift off the skin and discard it.) Remove the pan from the heat, add the chocolate chips, and let them sit in the hot cream mixture for about 30 seconds to soften, then whisk until all of the chocolate is melted and the filling is smooth. Stir in 1/2 teaspoon of the vanilla.

Transfer 3/4 cup of the truffle sauce to a large bowl and leave the remaining sauce in the pan, for topping the mousse. Set aside to cool to room temperature, about 30 minutes.

Have ready 6 stemmed glasses or goblets with at least a 10-ounce capacity.

In a large bowl, using an electric mixer on medium-high speed, beat the remaining 2 cups cold cream, the powdered sugar, instant coffee, and the remaining 1 teaspoon vanilla until firm peaks form. (The coffee will dissolve as the cream whips.) Transfer 1/2 cups of the whipped cream to a small bowl and set aside. Whisk about 1 cup of the remaining whipped cream into the cooled truffle sauce in the large bowl, then fold the remaining whipped cream into the mousse.

Spoon about 2 tablespoons of mousse into the bottom of each glass. Spoon about 2 tablespoons of the reserved coffee whipped cream over the mousse, spreading it to the edges of the glass. Repeat the layering with the mousse and coffee whipped cream. Use a small spoon to drizzle the reserved chocolate sauce over the top of each glass. (Warm the sauce briefly over low heat if necessary to make it pourable.)

Cover the mousse and refrigerate until cold and set, about 2 hours, or as long as overnight. Serve cold.

Choices Two tablespoons of rum can be whipped with the cream.