• 5 ounces bittersweet chocolate
• 2 ounces unsweetened chocolate
• 5 ounces (1¼ sticks) unsalted butter
• 3 tablespoons cornstarch
• ¾ cup plus 2 tablespoons sugar
• 4 eggs
• 4 egg yolks
• 1 tablespoon rum (or brandy)
• Oil or butter for coating ramekins
• Flour for dusting ramekins
• 1½ pints vanilla ice cream
Pour about ¾ inch water in the bottom of a double boiler, making certain top pan will not touch water. Bring the water to a boil, then reduce heat to simmer. Chop bittersweet and unsweetened chocolate into small pieces and place in the top of double boiler with butter and place over boiling water. Stir occasionally with a rubber spatula until chocolate and butter are completely melted and smooth. Remove from heat.
Sift cornstarch and sugar into a large bowl. In a medium bowl, whisk together the egg yolks and rum (or brandy), then whisk egg mixture into the cornstarch-sugar mixture all at once. Whisk in the chocolate-butter mixture. Cover and chill batter at least 2 hours, or overnight, before using.
Preheat oven to 350°. Lightly oil (or butter and flour) six 6-ounce ramekins or small soufflé dishes. Place ½ cup batter in each ramekin (a 4-ounce ice cream scooper dipped in hot water works nicely for this). Bake until barely risen and cracked on top, 10 to 14 minutes. Cool about 8 minutes before serving. Unmold onto plates and serve a scoop of ice cream on the side, or serve right in ramekins with a scoop of ice cream on top.