Lightly grease four 6-ounce ramekins with cooking spray or melted butter and dust with a little cocoa powder or flour to prevent sticking.

In a microwave-safe bowl, combine the chopped chocolate and butter. Microwave in 30-second intervals, stirring after each, until completely melted and smooth. Set aside to cool slightly.

In a separate medium bowl, whisk together the eggs, egg yolks, granulated sugar, and vanilla extract until light in color and slightly thickened.

Gradually fold the cooled chocolate mixture into the egg mixture until well combined. Sift in the flour and salt, then gently fold until just incorporated, being careful not to overmix.

Divide the batter evenly among the prepared ramekins. Place 1-2 ramekins (depending on your air fryer size) into the air fryer basket. Air fry at 350°F (175°C) for 10-12 minutes, or until the edges are set and the center is still slightly jiggly.

Carefully remove the ramekins from the air fryer. Let them cool for 1-2 minutes, then invert onto serving plates. Dust with powdered sugar if desired and serve immediately with ice cream or berries.