You can freeze leftover chicken or beef for many uses: quesadillas, burritos, casseroles, soup, stir-fry, or any other recipe that calls for chopped, cooked chicken. It saves you a lot of time! More ideas for leftovers:

Clean-out-the-Crisper Vegetable Soup

Rubber Chicken (or how to make one chicken into three great meals)

I add leftover chicken or ham to this recipe: Garlic Parmesan Egg Noodles.

Recycle that Roast!

Overnight Crock Pot Roast and Leftover Pot Pie