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

2. 2. In a microwave-safe bowl, melt the chocolate and butter together in 30-second intervals until smooth.

3. 3. In a separate bowl, whisk together eggs, egg yolks, sugar, and vanilla extract until well combined.

4. 4. Gradually fold the melted chocolate mixture into the egg mixture.

5. 5. Add flour and salt, and mix until just combined.

6. 6. Divide the batter evenly among the prepared ramekins.

7. 7. Bake for 12-14 minutes until the edges are set but the center is still soft.

8. 8. Carefully invert each ramekin onto a plate and serve warm with a dusting of powdered sugar and a scoop of vanilla ice cream.