In a skillet, cook ground beef, onion, garlic, oregano, salt and pepper at medium-high heat, stirring from time to time, 3 to 5 minutes or until beef is no longer pink. Drain any fat. Set aside. On a lightly floured surface, lower the dough in a circle of 12 inches of diameter. Put on a greased pizza plate. Spread sauce on the pizza dough. Garnish with beef preparation and sprinkle with cheddar and mozzarella cheeses. Cook on the lowest grill in a preheated oven of 500 F for about 10 minutes or until cheese is bubbling and crust is golden and slighly inflated.