1. Preheat the oven to 425°F (220°C) and grease individual ramekins with butter.

2. Melt chocolate and butter in a double boiler until smooth.

3. In a separate bowl, whisk eggs, egg yolks, and sugar until pale and fluffy.

4. Fold in the melted chocolate mixture and sift in flour until just combined.

5. Pour the batter into the prepared ramekins and bake for 12-14 minutes.

6. Let the cakes cool for a minute before flipping them onto plates. Serve warm with a scoop of vanilla ice cream.