In a medium bowl, combine potatoes, one egg, onion and black pepper. Divide potato mixture into 8 equal portions. Use your hands to form 1/2 inch thick patties. Dredge patties in flour, then in egg and coat with Panko Bread Crumbs. Meanwhile heat vegetable oil in a large skillet over medium high heat. Add potato patties to the hot oil. Cook until well browned, turn with a spatula and brown on the other side.