Prep the ramekins. Generously butter the inside of each ramekin, then dust with cocoa powder. Tap out the excess. This helps the cakes release easily and adds extra chocolate flavor.

Preheat the air fryer. Set it to 375°F (190°C) for about 3 minutes. A warm basket helps the cakes rise and set at the edges.

Melt chocolate and butter. In a heatproof bowl, microwave chopped chocolate and butter in 20–30 second bursts, stirring each time, until smooth. You can also do this over a double boiler.

Whisk eggs, yolks, and sugar. In a separate bowl, whisk the eggs, yolks, and sugar until slightly thick and lighter in color, about 30–45 seconds by hand. This adds a little volume.

Combine with chocolate. Slowly whisk the warm chocolate-butter mixture into the egg mixture. Add vanilla and salt. Stir until smooth.

Fold in flour. Sift or sprinkle in the flour and fold gently with a spatula just until no dry streaks remain. Don’t overmix.

Fill the ramekins. Divide the batter evenly among the prepared ramekins, filling each about three-quarters full.

Air fry. Place ramekins in the air fryer basket with space between them. Cook at 375°F (190°C) for 7–9 minutes. The tops should look set and matte, but the centers should jiggle slightly when you nudge the ramekin.

Rest briefly. Let the cakes sit for 1–2 minutes. This short rest helps them unmold without losing the molten center.

Unmold and serve. Run a thin knife around the edges. Invert each ramekin onto a plate and lift it off. Dust with powdered sugar, add ice cream or berries, and serve immediately for the best lava flow.