Preheat your air fryer to 380°F (193°C). While it's heating, pat the chicken breasts dry with paper towels.
In a shallow dish, mix together the breadcrumbs, grated Parmesan cheese, Italian seasoning, garlic powder, salt, and black pepper.
In another shallow bowl, beat the egg until well mixed.
Dip each chicken breast first into the egg wash, allowing any excess to drip off, then coat it in the breadcrumb mixture, pressing gently to adhere.
Lightly spray the air fryer basket with cooking spray. Arrange the breaded chicken breasts in a single layer, ensuring they do not overlap.
Air fry the chicken for 10 minutes. After 10 minutes, carefully flip the chicken over.
After flipping, spoon some marinara sauce over each piece of chicken and sprinkle the shredded mozzarella cheese on top.
Cook for an additional 5-7 minutes, or until the chicken is cooked through (internal temperature should reach 165°F/74°C) and the cheese is melted and bubbly.
Carefully remove the chicken from the air fryer. Garnish with fresh basil leaves before serving.