Preheat & Prepare:

• Preheat oven to 425°F (220°C).

• Grease 4 ramekins with butter and lightly dust with flour or cocoa powder.

Melt the Chocolate & Butter:

• In a heatproof bowl, melt butter and dark chocolate together over a double boiler or in the microwave (30-second intervals, stirring between each).

• Stir in chocolate-hazelnut spread until smooth.

Mix the Batter:

• In a separate bowl, whisk together eggs, egg yolks, sugar, vanilla, and salt until pale and slightly thickened.

• Gently fold the melted chocolate mixture into the eggs.

• Sift in flour and fold until just combined.

Fill & Bake:

• Divide batter evenly between the ramekins.

• Bake for 10-12 minutes—edges should be set but the center should still be soft.

Serve Immediately:

• Let cool for 1 minute, then carefully run a knife around the edges and invert onto plates.

• Garnish with powdered sugar, chopped hazelnuts, or a scoop of vanilla ice cream.