Preheat the oven to 400°F (200°C). Lightly grease a baking sheet or ensure your skillet is oven-safe.
Pat the chicken breasts dry and season both sides with salt and pepper. If thick, gently pound them to an even thickness.
Set up three shallow bowls:
Bowl 1: Flour
Bowl 2: Whisked eggs mixed with milk
Bowl 3: Parmesan cheese, breadcrumbs, garlic powder, onion powder, Italian seasoning, and lemon zest
Dredge each chicken breast in flour, shaking off excess. Dip into the egg mixture, then press firmly into the Parmesan breadcrumb mixture until well coated.
Heat olive oil (and butter, if using) in a large skillet over medium heat.
Sear the chicken for 2–3 minutes per side until the crust is golden brown.
Transfer the skillet to the oven (or move chicken to a baking sheet) and bake for 8–12 minutes, or until the internal temperature reaches 165°F (74°C).
Remove from oven and let the chicken rest for 5 minutes before serving. Garnish with parsley and lemon wedges if desired.