Enchalida Casserole

I have had this recipe for years. It was on Good Morning America one time. We have not had this in a long time but its easy enough to make for dinner tonight and I have all the stuff. Serving it with a green salad.
Ingredients
Casserole
1 package Doritos (13-ounce), save 2 cups for casserole topping
2 tbsp. onion, grated
1 10-ounce can chili with beans
10 to 15 ounce enchilada sauce
1 can tomato sauce (8 ounce)
1 1/2 cups shredded sharp cheddar cheese
Topping
2 cups Doritos
1/2 cup shredded cheddar cheese
1 1/4 cups sour cream

Cooking Directions
Preheat oven to 375° F.

Crumble 6 cups Doritos with your hands into a large mixing bowl.

Add the onion, the chili, the enchilada sauce, tomato sauce and 1½ cups of cheddar cheese to the crumbled Doritos. Stir with a rubber spatula to combine. Place mixture into an 8½ x 11-inch oven proof casserole dish. Bake for 20 minutes.

Remove from the oven. Spread the sour cream over the top of the casserole with a large spoon or rubber spatula. Top with remaining 2 cups Doritos. Then sprinkle with the 1/2 cup of the cheddar cheese.

Bake for another five minutes and serve.