Mexican Nacho Casserole

Nacho chips Cook ground beef and taco seasoning mix according to package directions. In bottom of a medium casserole, spread refried beans; sprinkle with onions. PLace meat over beans. Bake at 200ÂșC for 15 minutes. Tuck nacho chips around edge of casserole. Top with green pepper and grated cheddar cheese. Bake 5 minutes. Garnish with sour cream, chopped green onion and chopped tomato.