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

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

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

4. 4. Slowly pour the melted chocolate mixture into the egg mixture while whisking continuously.

5. 5. Add flour and salt to the mixture and gently fold 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. Remove from the oven and let it cool for 1-2 minutes before running a knife around the edges and inverting onto plates.

9. 9. Serve immediately with a scoop of vanilla ice cream or whipped cream on top.