Step 1

Adjust oven rack to middle position and preheat oven to 375°F. Butter seven 4-ounce ramekins (see note).

Step 2

Using microwave or a bowl set over pan of simmering water, melt chocolate with butter, stirring occasionally, until melted and smooth. Remove from heat.

Step 3

While chocolate is melting, whip eggs, sugar, and salt using mixer fitted with whip attachment on medium-high speed until mixture is lightened, about 5 minutes.

Step 4

Reduce speed to low and mix in chocolate mixture until combined. Spoon into cups and place on baking sheet. Bake until edges are set but center is underdone, about 10 minutes. Avoid over-baking. Let cool 3 minutes and serve.