This is a recipe I got from my mother-in-law that I modified. To make it quicker and easier, I just layer tortillas instead of rolling them. If you get a 9x13 rectangular foil pan, using 1 large tortilla normal and tearing another one, it fits well. So tortilla, filling, tortilla, filling, etc.
Do NOT put the sour cream on it before freezing. You will want to do that before cooking. This is one that you need to pull out to thaw the night before.
3-4 pounds shredded chicken (see my post called Cheap and Easy Shredded Chicken)
1/2 cup butter
1 1/2 cup chopped onions
2 cans Rotel tomatoes (10oz size)
1 can Stewed Tomatoes (28oz)
Bag of Large Tortillas
Bag of Small Tortillas
2 cups sour cream
Saute onions in butter
Drain tomatoes and drop in.
Add cheese while stirring a ton.
Preheat oven if not freezing. Cook on 350 degrees for 30 mins if thawed. If still frozen, I put on like 250 for 20 minutes first.