Solution: Because chocolate mousse derives almost all of its flavor from the starring ingredient, we wanted to nail down how much chocolate in proportion to eggs would give use a flavor we liked. We found that six ounces of chocolate provided the rich chocolate flavor we liked. We also discovered that butter gave the mousse more creaminess and density without obliterating the lightness. One cup of heavy cream, whipped and folded in, smoothed out the flavor without much diluting the chocolate impression. We also preferred a mousse made with unbeaten egg yolks. Beating them otherwise introduced more air into the mousse, which meant less flavor per mouthful.

For Good Measure: We tested adding various flavoring liquids, including strong coffee and a variety of liquors and liqeurs. Not surprisingly, all such additions made the final product less firm. More than two tablespoons of such liquid started to make the mousse slightly soupy. If you prefer a stronger alcohol kick, we recommend you try whipping some additional liquer into a whipped cream topping.

CHOCOLATE MOUSSE

Serves 6 to 8

For an extra creamy chocolate mousse, fold in one cup of heavy cream that’s been whipped instead of the one-half cup called for here. Make this mousse at least two hours before you wish to serve it to let the flavors develop, but serve it within twenty-four hours because flavor and texture will begin to deteriorate.

6 ounces bittersweet or semisweet chocolate, chopped coarse
4 tablespoons unsalted butter
Pinch salt
1 teaspoon vanilla extract
2 tablespoons strong coffee or 4 teaspoons brandy, orange-flavored liqueur, or light rum
4 large eggs, separated
2 tablespoons sugar
1/2 cup heavy cream, plus extra for garnish

1. Melt chocolate any of the following three ways: in medium bowl set over large saucepan of barely simmering water; in uncovered Pyrex measuring cup microwaved at 50 percent heat for 3 minutes, stirring once at 2 minute mark; or in ovenproof bowl set in 350-degree oven for 15 minutes. Whisk butter into melted chocolate, 1 tablespoon at a time; stir in salt, vanilla, and coffee or liquor until completely incorporated. Whisk in yolks, one at a time, making sure that each is fully incorporated before adding the next; set chocolate mixture aside.

2. Stir egg whites in clean mixing bowl set over saucepan of hot water until slightly warm, 1 to 2 minutes; remove bowl from saucepan. Beat with electric mixer set at medium speed until soft peaks form. Raise mixer speed to high and slowly add sugar; beat to soft peaks. Whisk a quarter of the beaten whites into chocolate mixture to lighten it, then gently fold in remaining whites.

3. Whip cream to soft peaks; gently fold into mousse. Spoon portion of mousse into six to eight individual serving dishes or goblets. Cover and refrigerate to blend flavors, at least 2 hours. (Can be covered and refrigerated up to 24 hours.) Serve with additional whipped cream.