Whisk together the marinade ingredients in a small bowl.
Brush the mushrooms on both sides with the marinade, leaving some marinade over at the end.
Place the mushrooms in the air fryer, tops down and gill side up. Air fry for 5 minutes at 400 °F (200 °C), then flip the mushrooms and air fry for another 4 - 7 minutes.
Serve as a snack, a vegetable side dish or transform these mushrooms into portobello burgers, slice and serve with tacos or make a pizza version!