Preheat oven to 425°F (220°C).

Butter six 6-ounce ramekins and dust them with sugar.

Melt chocolate in a double boiler or in the microwave in 30-second increments, stirring between each interval, until smooth.

Whisk together eggs and sugar until pale and thick, about 2-3 minutes.

Whisk in flour and salt until just combined.

Pour in melted chocolate and whisk until smooth.

Divide batter evenly among prepared ramekins.

Bake for 12-15 minutes, or until edges are set and centers are still slightly jiggly.

Remove from oven and let cool in ramekins for 1 minute.

Invert onto plates and serve immediately, with centers still molten and warm.