Cream the butter and sugars

• In a mixing bowl, beat the softened butter with the brown sugar and white sugar until creamy and smooth.
• Beat in the egg and vanilla extract until fully combined.

Mix the dry ingredients

• In another bowl, whisk the all-purpose flour with the baking soda, baking powder, cornstarch and salt.
• Add the dry mixture to the wet ingredients and stir until just combined.

Fold in the chocolate chips

• Fold the chocolate chips into the dough, keeping a few extra for the topping.

Fill the pan

• Spread the dough evenly in the round foil pan.
• Press a well in the center and add the melted chocolate for the filling, then cover with a little dough.
• Scatter the extra chocolate chips over the top.

Air fry

• Air fry at 160 °C until the edges are set and the center is still soft and scoopable.
• Let it cool slightly in the pan before serving with a spoon.