Ingredients

• 4 tablespoons unsalted butter
• 2 ounces high-quality bittersweet chocolate or 2 ounces semisweet chocolate, broken into pieces
• 1 large egg
• 1 egg yolk
• 3 tablespoons granulated sugar
• 1 pinch salt
• 2 tablespoons flour

Instructions

1. If making and serving the cakes at once, preheat oven to 425°F Butter two 3/4-cup ceramic ramekins or ovenproof glass custard cups.

2. In double boiler or in the microwave, melt butter with the chocolate, stirring to combine. Remove from heat immediately.

3. In medium bowl, whisk egg and yolk lightly, then add sugar and salt ans whisk until blended and slightly paler and thickened, about 1 minute.

4. Slowly whisk in the melted chocolate, in a stream, then whisk in flour.

5. Divide batter between buttered ramekins.

6. At this point, ramekins can be refrigerated for a day if preparing in advance; cover them loosely with plastic wrap once they're cool.

7. Bake cakes on a baking sheet in preheated oven about 10 minutes if preparing immediately, up to 14 minutes if baking after refrigerating. Go by appearance, rather than time: The cakes should be firm on the outside and dry across the top, but the center 1 inch or so should still be quite wobbly.

8. Remove from oven and let stand 1 minute. Run knife around sides to loosen, then turn them out onto individual serving plates.

9. Sift powdered sugar over them, if desired, and serve with a scoop of vanilla ice cream.