Mexican Beef Casserole

This was a good beef casserole that is a weight watchers recipe. We did add a little more chili powder, cumin and rep pepper flakes but I don't think it added any thing but a little more taste.
1 lb extra lean ground beef or sirloin
1/2 cup onions chopped (we used 1 onion)
1 can rotel tomatoes with chilies
1 can kernel corn drained
1 can black beans rinsed and drained
1 pkg taco seasonings mix
8 to 12 corn tortillas
3/4 cup nonfat sour cream
1/3 cup reduced fat Mex cheese shredded
1/3 bunch cilantro chopped to taste.
Brown ground beef and onions together for about 10 to 12 minutes, drain.
Add corn,beans,rotel tomatoes and taco seasonings mix well and simmer for 5 minutes.
Spray baking dish 2 quart 12x8 and place half of tortillas in bottom,
Spoon half of beef mixture on top, place sour cream over beef. Then layer last tortillas and then beef mixture.
Place in heated 350 oven and bake for 25 minutes remove from oven and and sprinkle with cheese.
We added some jalapeno peppers on top.
Cook for another 5 minutes or till cheese is melted. Let stand for 5 minutes and sprinkle with cilantro.
Salsa is our own see 6/28/08 for recipe