Preheat your oven to 425°F (220°C). This high temperature is crucial for achieving that ideal gooey center that we all crave in molten cakes.

Grease four ramekins with butter and dust lightly with flour. This step prevents the cakes from sticking and ensures they release beautifully when inverted.

Melt the bittersweet chocolate and unsalted butter together in a microwave-safe bowl. Do this in intervals of 20 seconds, stirring after each burst until the mixture is smooth and silky.

Whisk the eggs, egg yolks, and granulated sugar in another bowl. Beat these together until the mixture becomes pale and fluffy, which creates a lovely airy texture.

Combine the melted chocolate mixture with the egg mixture. Pour it in gradually while stirring gently to maintain that airy consistency and ensure everything is well blended.

Fold in the flour, vanilla extract, and a pinch of salt until just combined. Avoid over-mixing; you want to keep the batter light and fluffy for that perfect lava effect.

Divide the batter evenly among the prepared ramekins, filling each two-thirds full. This allows for enough space for the cakes to puff up and create that molten center.

Bake for 12-14 minutes until the edges are firm but the centers remain soft. Keep an eye on them; they should look set around the edges while still wobbly in the middle.

Cool briefly before inverting the ramekins onto plates. Let them sit for about a minute to make sure they release effortlessly, then serve them warm to enjoy the ooey-gooey inside!