
Man, do I love turning day-old chicken into something absolutely mouthwatering! This Leftover Chicken and Potato Casserole has become my ultimate comfort dish. Every spoonful combines juicy chicken, rich mushroom gravy and filling potatoes for a dinner that'll make you forget you're eating leftovers.
Special Yet Simple
The best thing about this dish is how it transforms yesterday's meal into something the whole family gets pumped about. That velvety white gravy pulls all the flavors together, and you can toss in whatever veggies or extras you've got hanging around to make it yours.
Round Up Your Supplies
- Mushrooms: Fresh sliced ones bring earthy goodness and substance.
- Butter: Go for unsalted when cooking and for the optional crunchy topping.
- All-Purpose Flour: This makes your mushroom sauce nice and thick.
- Onions: Diced onions create a tasty foundation.
- Milk (or Half-and-Half): This makes everything wonderfully creamy.
- Cooked Chicken: Chunks of leftover roasted or rotisserie chicken work great.
- Cooked Potatoes: Cubed leftover baked or boiled potatoes.
- Shredded Cheese (Optional): Some cheddar or Monterey Jack adds extra yumminess.
- Breadcrumbs (Optional): Fresh crumbs mixed with melted butter give you that irresistible crunch on top.
Whipping Up Warmth
- Step 6 - Bake
- Put it in the oven for 25-30 minutes until everything's hot and bubbling. Dig in right away.
- Step 5 - Add the Topping
- For breadcrumbs, mix 1 cup of soft crumbs with 2 tablespoons of melted butter. Or just sprinkle 1 cup of shredded cheddar on top if that's more your style.
- Step 4 - Assemble the Casserole
- Mix 2 cups of cubed cooked potatoes and 2 cups of chicken chunks with your mushroom sauce in the greased dish. Give it a gentle stir.
- Step 3 - Make the Sauce
- Add 2 tablespoons of flour and cook for 1-2 minutes. Slowly pour in 1 cup of milk while stirring non-stop until it gets thick, about 3-5 minutes. Throw in some salt and pepper to your liking.
- Step 2 - Sauté the Vegetables
- Melt 3 tablespoons of butter in a pan over medium heat. Toss in your sliced mushrooms and chopped onions, cooking them for around 8 minutes until they're soft and golden.
- Step 1 - Preheat the Oven
- Get your oven going at 350°F (180°C) and lightly grease a 2-quart baking dish.
Insider Tips
After making this tons of times, here's what I've figured out: Pour your milk in gradually to keep the sauce smooth, and always taste before it goes in the oven since everything's already cooked. No baking dish? A skillet that can go in the oven works just fine. Just don't put cold glass straight into a hot oven!
Tasty Twists
I'm always playing around with extra stuff to throw in. Sometimes I'll add a handful of frozen peas or some leftover broccoli. Fresh herbs like parsley or thyme really wake up the flavors. And don't get me started on toppings - those crunchy french-fried onions are amazing!
Storage Smarts
This dish is super handy for busy nights. You can put it all together and keep it in the fridge overnight, or even stick it in the freezer for up to a month. Just cook it a bit longer if it's coming straight from the cold.

Delightful Companions
We always serve this with a fresh green salad to cut through the richness. Some quick sautéed spinach or whatever veggies are in season work great too. It's all about creating that perfect comfort food moment right at your table!
Frequently Asked Questions
- → What type of potatoes should I use?
- Any cooked potatoes work! Roasted or boiled hold shape best, but mashed can be spread as a layer. Waxy options like yellow or red stay firmer than russets.
- → Can I prepare the dish in advance?
- Definitely! Put it together a day ahead, refrigerate, and bake right before serving. If cold, add 10-15 extra minutes to bake time. Add the topping just before baking.
- → What can I swap for mushrooms?
- If you’re not into mushrooms, try diced carrots, celery, peas, or even frozen mixed veggies. Stick to about a cup to keep the sauce balance right.
- → Can the bake be frozen?
- Yes, but cream sauce changes texture when frozen. Freeze without toppings and bake later. Thaw overnight, top, then bake for best results.
- → What’s a good alternative to half-and-half?
- Whole milk if you want lighter, heavy cream if richer is better. For dairy-free, use unsweetened almond or oat milk but adjust the flour for thickness.
Conclusion
Use up those leftovers in a cozy chicken potato bake.With tender chicken, a creamy mushroom sauce, and a touch of crunch on top, this hearty dish will satisfy the whole family.