Place chicken breasts between two sheets of plastic wrap and pound to an even 1/2-inch thickness with a rolling pin or heavy skillet. Pat dry with paper towels.

In a shallow bowl, whisk together flour, garlic powder, onion powder, salt, and pepper. In a second bowl, beat the egg with water. In a third bowl, mix panko and 1/4 cup Parmesan.

Dredge each chicken piece first in the flour mixture (shake off excess), then dip in the egg mixture, then press into the panko-Parmesan mixture, coating both sides evenly. Set on a plate.

Heat 2 tablespoons olive oil in a large oven-safe skillet over medium-high heat until shimmering. Add the breaded chicken (work in batches if needed—do not overcrowd). Cook 3-4 minutes per side, until golden brown and internal temperature reaches 165°F. Transfer to a plate and tent with foil.

Reduce heat to medium. Add remaining 1 tablespoon olive oil and butter to the skillet. Once butter melts, add onion and cook 3-4 minutes until softened. Add garlic and cook 30 seconds until fragrant.

Stir in crushed tomatoes, oregano, basil, and red pepper flakes (if using). Scrape up any browned bits from the bottom. Cook 2 minutes, stirring occasionally.

Add the pasta and chicken broth to the skillet. Stir to combine. Bring to a simmer, then reduce heat to medium-low, cover, and cook 12-14 minutes, stirring twice, until pasta is al dente and most liquid is absorbed. If too dry, add a splash of broth or water.

While pasta cooks, preheat the broiler with a rack about 6 inches from the heat source.

Slice the cooked chicken breasts into 1/2-inch strips. Arrange the strips on top of the pasta. Lay mozzarella slices over the chicken.

Transfer the skillet to the oven and broil 2-3 minutes, until cheese is melted and bubbly with golden spots. Watch closely to avoid burning.

Remove from the oven, let rest 2 minutes. Garnish with fresh basil and extra Parmesan. Serve directly from the skillet.