In a medium-sized, microwave-safe bowl melt the butter and chocolate chips in the microwave at 30-second increments then stir and continue until fully melted.
In a separate bowl combine the eggs, sugar, gluten-free flour, cocoa powder, and salt. Whisk well until combined.
Pour in the melted chocolate mixture and continue to whisk until fully mixed.
Spray 3 12oz ramekins with non-stick spray. If you want smaller servings, use 6 4oz ramekins.
Fill each ramekin about halfway with batter.
Place in air fryer, if using 12oz air fry at 375°F for 12-15 minutes, if using 4oz air fry at 375°F for 10-12 minutes.
The inside of the cake should still be gooey, but the internal temperature of the cake should be at least 165°F to be considered done.
Once done, let cool for 5 minutes.
Carefully scrape the sides to release the cake from the ramekin. Place a plate on top of the ramekin and flip the cake or invert the cake to release. The bottom of the cake will become the top of the cake.
Serve with powdered sugar or fresh fruit.