Warm chocolate cake with a gooey center, served with vanilla ice cream.
Preheat the oven to 425°F (220°C). Grease four ramekins with butter and dust them with flour.
In a microwave-safe bowl, combine the bittersweet chocolate and unsalted butter. Microwave in 30-second intervals, stirring between each, until the chocolate and butter are completely melted and combined.
Stir in the powdered sugar until well combined. Add the eggs, egg yolks, and vanilla extract, mixing until fully incorporated. Finally, fold in the flour and a pinch of salt until just combined.
Divide the batter evenly among the prepared ramekins.
Place the ramekins on a baking sheet and bake for 12-14 minutes, or until the edges are firm but the center is still soft.
Let the cakes cool for 1 minute, then carefully invert them onto plates. Serve warm with a scoop of vanilla ice cream on top.