Tamara's Chicken Enchilada Casserole

3/4 cup onion, chopped
1 can (14 oz.) mild enchilada sauce
2 cans (10.4 oz.) chopped tomatoes
2 cans (4 oz.) chopped green chilis
1/2 cup almonds, sliced
3 cups Monterey Jack cheese, shredded
6-8 boneless chicken breast halves, cooked and cubed
10 corn tortillas (6"), torn into pieces
1 tsp. ground cumin
1 1/2 tsp. garlic powder
1/2 tsp. Salt
2 tsp. ground oregano

Mix all ingredients together except the tortillas and cheese. Spray bottom of 13X9 baking dish with Pam. Alternate layers of tortillas, meat mixture and cheese. Bake at 350 for 30 minutes. Let cool for 10 minutes before serving. Top with chopped green onions. Serves 6-8.