Cut a circle out of a piece of paper. Place it in the baking pan.
Mix the butter and graham cracker crust together and press into the baking pan. Place the baking pan in the airfryer and cook for 4 minutes at 180 degrees.
In a mixer, blend cream cheese and add the sugar. Add one egg at the same time until creamy. Add the vanilla and mix well.
Remove the fry basket and pour the cheese mixture on top of the crust.
Place into the airfryer and cook for 15 minutes at 160 degrees. Cool for 3 hours before serving.
Whisk together the egg, yoghurt, milk, oil and vanilla. Stir through the caster sugar and mix until combined.
Sift in the flour and cocoa powder, then add the salt and most of the chocolate chips. Stir until just combined, with no floury streaks.
Arrange the cake cases and scoop batter evenly into each case. Sprinkle the reserved chocolate chips on top.
When preheated, remove the basket from the airfryer and put the cake cases into it. Arrange them close together, just touching.
Bake for 12-15 minutes until well-risen and the tops of the muffins spring back when pressed. Lift out of the airfryer and allow to cool on a wire rack for 15 minutes before serving.