Spray six 6-oz. ramekins or custard cups with vegetable oil cooking spray. Combine flour, cocoa, and baking powder in small bowl. Stir with whisk until blended and reserve. Melt chocolate in a small, heavy saucepan over low heat. Add butter and sugar and stir until smooth. Transfer mixture to a large bowl and, with an electric mixer at medium speed, beat in eggs, one at a time. Add espresso and reserved flour mixture. Continue beating until fully mixed. Raise mixer speed to high and beat mixture for 6 minutes more, until thickened. Pour even amounts of batter into prepared ramekins. Cover ramekins tightly with plastic wrap and freeze overnight, or up to 2 weeks ahead.

Approximately one hour before you want to serve, pre-heat oven to 375°F. Meanwhile, prepare the raspberry sauce. Combine raspberries and sugar in food processor. Blend until smooth. Strain puree through a sieve to eliminate the seeds. Stir in raspberry liqueur, if desired, and reserve. Remove ramekins from freezer and unwrap. Bake in oven for 18 to 20 minutes until sides are set but the center is still moist. Cool on wire rack for 5 minutes, then invert onto individual dessert plates. Let rest another 10 minutes and serve each one with a spoonful of raspberry sauce and a small scoop of ice cream. Garnish with fresh raspberries and dust with confectioner's sugar. Makes 6 servings.