Cook onions and garlic until soft. Add chicken and cook until almost done. Add tomato sauce. Cook chicken mixture until almost all tomato sauce is cooked away. (Chicken will be done then.) Warm tortillas on skillet. Put chicken and whatever condiments you choose into burrito and enjoy.
I also like to make this one into a chicken quesadilla. Just cook chicken the same as above and when done warm tortilla on skillet add chicken and shredded cheese fold over heat on both sides until cheese is melted and enjoy.