Preheat oven to 400 degrees F (205 degrees C).
In one mixing bowl, mix Seasoned Breadcrumbs (2 cup), Grated Parmesan Cheese (3 tablespoon), All-Purpose Flour (3 tablespoon), and Salt and Pepper (to taste). In another, add Egg (2).
Coat the Boneless, Skinless Chicken Breast (4) first in the egg, then in the breadcrumbs.
Into a skillet over medium high, add Unsalted Butter (4 tablespoon). Once melted and bubbling, add the chicken. Cook for 2-3 minutes on each side.
Coat chicken with Marinara Sauce (1 1/2 cup). Sprinkle generously with Grated Parmesan Cheese (to taste) and Shredded Mozzarella Cheese (to taste).
Bake for 5 minutes, until cheese is melted and bubbly.
Serve warm in the Potato Bun (to taste).