Yield: 8 portions
Unsalted butter - divided 6 Tbsp.
Sugar - 3/4 cup
Bittersweet chocolate - 6 oz.
Large eggs - separated 6
Ganache ball (recipe follows) - as needed
Using 2 Tbsp. butter, grease 8 6-oz. custard cups or ramekins. Use 1/4 cup sugar to dust cups; reserve.
In double boiler, melt chocolate and remaining butter; stir until smooth. (Alternately, microwave the mixture, checking and stirring at 30-second intervals.) Let cool.
Whip egg yolks until thick and lightly colored and tripled in volume; reserve. Whip egg whites until they are on the verge of forming very stiff peaks. Add remaining sugar; whip until very stiff peaks form; reserve.
Stir some cooled chocolate into egg yolks. Add remaining chocolate. Gently fold egg whites into chocolate mixture.
Pour small amount of batter into each custard cup. Place 1 ganache ball in cup. Add batter until cup is 4/5 full. Bake in oven preheated to 325F for 20-25 minutes, checking periodically, until cake is crusty on top but still gooey in center. Let rest 5-6 minutes. Use small knife to loosen cake. Invert onto dessert plate. Serve warm with crème anglaise, if desired.
Scald 1/2 cup cream in small saucepan over medium-high heat. Remove to bowl. Add 4 oz. finely chopped bittersweet chocolate and 1/8 cup strong espresso. Stir until chocolate is melted and mixture is smooth. Refrigerate until firm, about 1 hour. Form into 8 1-in. ball; reserve cold until use. Store up to 1 week refrigerated.