These warm, bittersweet puffs have coffee in them, but you'd never know it. Performing culinary sleight of hand, the hidden ingredient just helps chocolate taste more chocolatey, like a capful of vanilla would, but with a darker intent.
Soufflés are a dinner-party stunner. To serve them warm to guests, plan to start the recipe before eating and "pause" your cooking after Step 3. Leave the chocolate-egg mixture out and preheat the oven while you eat, then whip the egg whites and bake the soufflés after dinner.