Clean the Mushrooms: Submerge the mushrooms in a bowl of water to remove any dirt. Once clean, either allow them to air dry or gently pat them dry with a towel.
Prepare the Mushroom Caps: Remove the stems from all the mushrooms. Set aside 5-8 caps for the stuffing mixture and reserve the rest for filling.
Chop the Peppers: Clean and roughly chop the red sweet peppers into large chunks.
Make the Stuffing: In a food processor, combine the chopped red peppers, minced garlic, reserved mushroom caps, and shredded mozzarella. Process until the mixture is finely chopped and well-combined, making it easy to stuff into the mushrooms.
Stuff the Mushrooms: Spoon the stuffing mixture into each of the reserved mushroom caps, pressing lightly to ensure they are well-filled.
Preheat the Air Fryer: Preheat your air fryer to 375°F (190°C) for about 3-5 minutes.
Air Fry the Mushrooms: Place a piece of parchment paper in the air fryer basket and arrange the stuffed mushrooms in a single layer. Depending on the size of your air fryer, you may need to cook them in batches. Cook for 10 minutes, or until the mushrooms are tender and the stuffing is heated through.
Serve: Once cooked, remove the mushrooms from the air fryer and serve immediately. For added flavor, you can sprinkle with additional shredded cheese or panko breadcrumbs before air frying.