01 - Preheat oven to 425°F. Generously butter four 6-ounce ramekins and dust with cocoa powder, tapping out the excess.
02 - Melt chocolate and butter together in a heatproof bowl set over simmering water or in 30-second intervals in the microwave, stirring until smooth. Allow to cool slightly.
03 - Whisk whole eggs, egg yolks, and powdered sugar in a medium bowl until pale and thick, about 2 minutes.
04 - Stir melted chocolate mixture and vanilla extract into the egg mixture until fully combined.
05 - Sift in flour and salt, folding gently until just incorporated, avoiding overmixing.
06 - Divide batter evenly among prepared ramekins and place them on a baking sheet.
07 - Bake for 11 to 12 minutes until edges are set but centers remain soft and slightly jiggly.
08 - Let rest for 1 minute, then run a thin knife around edges and invert onto plates. Serve immediately with vanilla bean ice cream and garnish with berries, mint, and a dusting of powdered sugar if desired.