Place the mustard, ham, and cheddar between two slices of bread.
Butter the outside of each sandwich.
Place in the air fryer and use a toothpick to hold the sandwich in place.
Cook 4-6 minutes or until golden on the outside and melted inside.
Notes
Prep ahead and store in the refrigerator for 2-3 days until ready to cook.Reheat leftovers in a 325°F air fryer for 4 minutes or until heated through. Use a toothpick to hold the sandwich in place.