Preheat your oven to 425°F (220°C) and butter and flour five 6-ounce ramekins, tapping out any excess flour.

Melt the butter and dark chocolate in a heatproof bowl over a saucepan of simmering water or in the microwave, stirring until smooth.

In a separate bowl, whisk together the eggs, egg yolks, and granulated sugar until light and creamy.

Gradually fold in the flour and salt into the egg mixture until just combined.

Gently fold the melted chocolate mixture into the egg mixture until well incorporated.

Pour the batter evenly into the prepared ramekins.

Bake for 12-15 minutes, or until the edges are set but the center remains gooey.

Carefully remove the ramekins from the oven and let them cool for a few minutes before inverting them onto serving plates.

Dust with powdered sugar and garnish with fresh berries or a scoop of vanilla ice cream, if desired.