2 large eggs 1/4 cup milk 1/2 cup all-purpose flour 2 cups panko (Japanese bread crumbs), finely crushed in a food processor Four 8-ounce skinless, boneless chicken breast halves, pounded 3/4 inch thick Salt and freshly ground pepper 3/4 cup canola oil 1 1/2 cups tomato sauce 1/4 cup freshly grated Parmigiano-Reggiano cheese 1 cup shredded mozzarella 2 ounces sliced pepperoni 2 tablespoons chopped flat-leaf parsley