Prep the chicken: Pat the chicken dry. If using large breasts, slice horizontally to create thinner cutlets, then pound gently to even thickness (about 1/2 inch). This helps them cook evenly and stay juicy.
Season generously: In a small bowl, mix salt, pepper, garlic powder, onion powder, Italian herbs, and smoked paprika.
Rub the chicken with olive oil, then coat all sides with the seasoning blend.
Pan-sear for flavor (optional but recommended): Heat a large skillet over medium-high. Lightly sear the chicken 1–2 minutes per side to develop color. You’re not cooking it through—just building flavor.
Build the dish: Lightly spray a 9x13-inch baking dish.
Spread 1 cup marinara on the bottom. Nestle the chicken on top. Spoon the remaining marinara evenly over the chicken.
Add the cheeses: Sprinkle half the mozzarella over the sauced chicken.
Top with half the Parmesan.
Make the crunchy topping: In a bowl, combine panko, remaining Parmesan, a pinch of salt and pepper, and the optional whey isolate. Drizzle with 1 tablespoon olive oil and toss to coat.
Top and bake: Scatter the crumb mixture evenly over the chicken. Finish with the remaining mozzarella.
Mist lightly with cooking spray for extra crisping.
Bake: Place in a 400°F (200°C) oven for 18–25 minutes, until the chicken reaches an internal temperature of 165°F (74°C) and the top is golden and bubbly. Thinner cutlets lean toward 18 minutes; thicker pieces take longer.
Rest and garnish: Let it rest 5 minutes so the juices settle. Sprinkle with chopped basil or parsley.
Add red pepper flakes if you like a kick.
Serve smart: Pair with steamed broccoli, a simple salad, roasted zucchini, or high-protein pasta. Spoon extra sauce from the dish over each portion.