Add refried beans to one half of a tortilla, top with some grated cheese and fold the tortilla in half creating a half circle.
Press the tortilla down firmly to ensure it sticks and lightly brush both sides of the tortilla with a small bit of oil. Repeat with the remaining tortillas.
Preheat the air fryer to 365°F / 185°C and set the time to 8 minutes.
Place one or two tortillas in the preheated air fryer basket. Air fry for 4 minutes, flip the tortilla and press it down using a spatula to ensure it sticks. Air fry for a further 4 minutes.
Repeat with any remaining tortillas. Cut the quesadillas into triangles and serve with guacamole.