Clean and halve the Brussels sprouts and red radishes. Cut the onion into squares. Place them on a tray, sprinkle with walnuts, drizzle with olive oil, and add garlic salt. Toss to combine.

Sprinkle shredded cheese on top and place in the air fryer. Cook the turkey bacon in the air fryer until golden, then cut into bite-sized pieces.

After about 7 minutes, remove the tray, sprinkle the turkey bacon on top, and return to the air fryer for about 5 more minutes. Serve hot with vegetables.