In a large, deep skillet over medium heat, cook ground beef until nearly done.
Add next 9 ingredients (oregano through cauliflower) and cook for 5 to 7 minutes or until vegetables are tender-crisp. Add tomatoes and tomato sauce and bring mixture to a light boil; cook for an additional 5 minutes.
Serve immediately, topping each serving with Mozzarella cheese. Enjoy!