Preheat the air fryer to 380F.

In a small bowl mix together mayonnaise and mustard.

Spread the mayo mixture on one side of a slice of bread. Place the bread in the air fryer basket buttered side down.

Place two slices of cheese on top of the bread slice.

Spread the mayonnaise mixture on another slice of bread and place it on the cheese buttered side up. If you want to secure the sandwich together with a toothpick to make sure the bread doesn’t shift during cooking. Just push a toothpick through the center of the sandwich.

Air fry the grilled cheese for 6 minutes.

Gently flip the sandwich to the other side and fry for another 6 minutes, or until the bread is golden brown and the cheese is melted.

Repeat with additional bread and cheese to create more sandwiches.

Serve the grilled cheese hot while it remains soft or even stretchy.