Place tater tots in an ungreased 9x13 pan. Bake, uncovered, at 400 for 10 minutes.
Meanwhile, in a large skillet, cook beef over medium heat until no longer pink; drain. Stir in broccoli, soup, tomato, 3/4 c. french-fried onions, 1/2 c cheese, milk, garlic powder and pepper. Heat through. Pour over tater tots.
Cover and bake for 20 minutes. Uncover; sprinkle with remaining onions and cheese. Bake 5-10 minutes longer or until cheese is melted.