Enchilada Bake

1 1/2 lbs ground beef. 1/4 c. chopped onion (browned in the beef). 16oz. tomatoe sauce. 2 tsp. chili powder. Corn tortillas. 2 c. shredded cheese. 1/2 c. chopped tomatoes. 1/4 sour cream. Brown beef with onions and drain. Add tomatoe sauce and chili powder. Then make layers in a 8x8 casserole dish starting with tortillas, then beef and finally cheese. Make as many layers as you want. Bake in oven at 400 long enough to melt the cheese. Then take out of the oven and arrange tomatoes and sourcream on top. Serve and enjoy! This is such a simple dish to make and easy on the budget yet has such amazing flavor and is kid freindly too!!!