Gooey Chicken Burritos

2 large chicken breasts
1 (12 ounce) jar salsa (heat desired)
1 can cream of chicken soup
1 can mild diced green chiles
1 1/2 cups grated Cheddar and jack blend cheese
1 small onion
2 tablespoons tapioca or cornstarch (optional)
Flour tortillas

Combine all ingredients, except tortillas, in crock pot. Cook on LOW for 8 hours. Spoon onto warmed tortillas and roll burrito-style.