4 ounces semisweet chocolate, chopped
1-1/2 ounces unsweetened chocolate, chopped
10 Tablespoons unsalted butter, softened
1/2 cup plus 2 Tablespoons sugar
3 eggs, lightly beaten
1/2 cup plus 2 Tablespoons flour
1-1/2 Tablespoons baking cocoa
3/4 teaspoon baking powder
Coat six 3/4– to 1-cup ramekins lightly with butter. Combine the semisweet chocolate and unsweetened chocolate in the top of a double boiler. Heat over barely simmering water until smooth, stirring constantly. Add the unsalted butter and sugar. Heat until the butter melts and the sugar dissolves, stirring frequently. Pour the chocolate mixture into a large mixing bowl.
Add the eggs, flour, baking cocoa and baking powder to the chocolate mixture and mix well. Beat for 8 minutes or until thickened and of a mousse consistency. Spoon the chocolate mixture evenly into the prepared ramekins. Freeze, covered with plastic wrap, for 3 hours or longer. You may prepare up to this point 3 days in advance; remove the plastic wrap.
Arrange the ramekins on a baking sheet on the center oven rack. Bake at 375 degrees for 14 minutes or until the edges are set and the tops are moist and shiny. Do not overbake. Let stand for 10 minutes. Invert onto individual dessert plates. Serve warm with ice cream or whipped cream.