Easy Leftover Chicken and Potato Casserole

Leftover chicken casserole in baking dishes
The Spruce
Prep: 15 mins
Cook: 45 mins
Total: 60 mins
Servings: 4 servings
Nutritional Guidelines (per serving)
915 Calories
53g Fat
57g Carbs
52g Protein
See Full Nutritional Guidelines Hide Full Nutritional Guidelines
Nutrition Facts
Servings: 4
Amount per serving
Calories 915
% Daily Value*
Total Fat 53g 68%
Saturated Fat 26g 128%
Cholesterol 193mg 64%
Sodium 1091mg 47%
Total Carbohydrate 57g 21%
Dietary Fiber 6g 22%
Protein 52g
Calcium 450mg 35%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)

This casserole is easy to prepare with leftover chicken and potatoes. It makes a nice everyday meal using the leftovers from a Sunday chicken dinner, a cooked rotisserie chicken, or leftovers from roasting a whole bird. Cook the diced potatoes separately.

Leftover chicken can become dry and a little blah but combining it with a creamy sauce and baking until bubbly gives it new life. Revive your leftovers by turning them into a totally new dish that the whole family will love.

Top the chicken casserole with a cup of shredded cheddar cheese or crunchy buttered breadcrumbs. Crushed french fried onions would be delicious as well.


Click Play to See This Leftover Chicken and Potato Casserole Recipe Come Together


  • 3 tablespoons butter
  • 8 ounces mushrooms (sliced)
  • 1 cup onions (chopped)
  • 2 tablespoons all-purpose flour
  • 1 cup milk (or half-and-half)
  • Freshly ground black pepper (to taste)
  • Kosher salt (to taste)
  • 2 cups diced potatoes (cooked)
  • 2 cups diced chicken (cooked)
  • Optional: 1 cup soft breadcrumbs
  • Optional: 2 tablespoons butter (melted)
  • Optional: 1 cup cheddar cheese (shredded; or Monterey Jack cheese)

Steps to Make It

  1. Gather the ingredients. Preheat the oven to 350 F / 180 C / Gas Mark 4.

    Ingredients for leftover chicken casserole
    The Spruce
  2. Lightly grease a 1 1/2-quart baking dish.

    Lightly greased casserole dish
    The Spruce
  3. Heat the butter in a large, heavy skillet or sauté pan over medium heat. Add the mushrooms and onions, and cook until tender and lightly browned, about 8 minutes.

    Sautéing the onions and mushrooms, while stirring it with a wooden spoon
    The Spruce
  4. Stir the flour into the pan. Cook, stirring, for 1 to 2 minutes.

    Cooking the onions and mushrooms until lightly browned
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  5. Gradually add the milk or half-and-half, stirring, and cooking until thickened. Add pepper and salt.

    Adding milk to the sauté pan, while stirring it with a wooden spoon
    The Spruce
  6. In the prepared baking dish, combine the cooked potatoes, chicken, and mushroom sauce mixture. 

    Chicken, potatoes, and mushroom in a baking dish
    The Spruce
  7. If using the breadcrumb topping, toss the breadcrumbs with the melted butter until well coated.

    Breadcrumbs with melted butter in a bowl
    The Spruce
  8. Top the casserole with the buttered breadcrumbs or sprinkle with shredded cheese.

    Two casseroles with cheese, ready to be baked
    The Spruce
  9. Bake for 25 to 30 minutes or until hot and bubbly. Enjoy.

    Leftover chicken and potato casserole, ready to serve
    The Spruce

Recipe Variations

  • Other cooked vegetables may be used along with the potatoes. Add 1/2 cup or more of diced cooked rutabaga or carrots either in place of or in addition to the mushrooms.
  • Add a big handful of frozen peas or frozen spinach that has been thawed, squeezed dry, and chopped.
  • Bring in extra flavor by adding herbs and spices along with the salt and pepper. Basil, garlic, oregano, paprika, and parsley are good choices for this dish.

How to Store and Freeze

  • If well wrapped, this casserole can be stored in the fridge for up to a day before baking, or frozen for a month. Defrost in the refrigerator overnight before baking and add 5 minutes to the cooking time.
  • Leftover cooked chicken will last up to 4 days in an airtight container in the refrigerator. It can also be stored in the freezer for up to a month. Defrost overnight in the fridge before using and use right away upon thawing.

Glass Bakeware Warning

For premade casseroles or leftovers that are in a glass baking dish and have been refrigerated, do not place directly into a hot oven as the glass can shatter. Instead, place any cold glass bakeware into a cold oven to warm up while it preheats. Or, allow the bakeware to rest outside of the fridge for 30 minutes to reach room temperature while the oven preheats.