Mix the breadcrumbs, Parmesan cheese, and garlic powder in a shallow dish.
Dip each chicken breast in beaten eggs, then press into the breadcrumb mixture to coat both sides evenly.
Heat olive oil in a large skillet over medium-high heat and cook the chicken for 4 to 5 minutes per side until golden brown and cooked to 165°F / 74°C.
Preheat the oven to 400°F / 200°C, place the cooked chicken on a baking sheet, spoon marinara sauce over each piece, and top with mozzarella cheese.
Bake for 8 to 10 minutes until the cheese is melted and bubbly.
Rest for 3 minutes before serving to let the juices settle and the cheese set.