Southwestern Lasagna

1 1/2 pounds hamburger

1 chopped onion

1 can enchilada sauce

1 can diced tomatoes

1 tsp salt

1/4 tsp garlic powder

1/4 tsp pepper

1 cup ricotta cheese

1 egg

1/2 pound Monterey jack cheese, thinly sliced

8 corn tortillas, halved

1/2 cup shredded cheddar cheese

Brown hamburger and onion; drain fat.  Stir in enchilada sauce, tomatoes, salt, garlic powder, and pepper.  Bring to a boil; reduce heat and simmer for 20 minutes.  In a small bowl, combine ricotta and egg; set aside.  Spread 1/3 of meat sauce in greased 13x9 pan.  Top with half of the Monterey jack cheese, half of the ricotta cheese and half of the tortillas.  Repeat layers.  Sprinkle with cheddar cheese.  Cover and back at 350 for 30 minutes.