1Heat oven to 425°.
2Cook beef in 10-inch skillet over medium heat 8 to 10 minutes, stirring occasionally, until brown; drain. Stir in pizza sauce. Heat to boiling; reduce heat to low and keep warm.
3Beat eggs, milk, oil, flour and salt with wire whisk until foamy. Spoon beef mixture into ungreased rectangular baking dish, 13x9x2 inches. Sprinkle with cheese. Pour egg mixture over cheese. Sprinkle with onions.
4Bake uncovered 25 to 30 minutes or until puffy and golden brown. Serve immediately.