Heat oven to 325. Brown Ground beef and add taco seasoning and water, according to packet instructions. Set aside

In a separate bowl, combine sour cream, mayo, 1 cup of cheese, and half the onions. set aside

Layer the Tortillas on the bottom and sides of a 9X13 casserole dish. You may need an additional tortilla to cut and cover bottom and sides.

Saute remaining onions and bell peppers until slightly tender.

On top of Tortillas, evenly distribute ingredients in the following order: ground beef, tomato slices, green pepers, onions, jalapeno peppers, sour cream mixture and end with remaining shredded cheese.

Bake 30 - 40 minutes or until edges of tortillas are lightly browned.