About 1 tablespoon butter for the dish
1/3 cup sugar, plus some for the dish
2 ounces good quality bittersweet chocolate, melted
3 eggs, separated
1/4 teaspoon tartar
-Heat the oven to 350°F. Butter two 2-cup or one 4-cup soufflé or other deep baking dish(es). Sprinkle each with sugar, invert it, and tap to remove excess sugar.
-Whisk the egg yolks with the all but 1 tablespoon of sugar until very light and very thick; the mixture will fall in a ribbon from the ends of the beaters when it is ready. Mix in the melted chocolate until well combined; set aside.
-Beat the egg whites with the salt and tartar until they hold soft peaks; continue to beat, gradually adding the remaining tablespoon of sugar, until they are very stiff and glossy. Stir a good spoonful of the whites thoroughly into the egg yolk mixture to lighten it; then fold in the remaining whites, using a rubber spatula. Transfer to the prepared soufflé dishes (at this point you can cover and refrigerate the soufflés until you’re ready to bake them).
-Bake until the center is nearly set, 20 minutes for individual soufflés and 25 to 35 for a single large soufflé. Serve immediately.
From: Mark Bittman