Chicken Mushroom Casserole Recipe

This creamy, comforting Chicken Mushroom Casserole is made with tender chicken breasts, earthy cremini mushrooms, and ready in 45 minutes. Seeing the golden, bubbly cheese pull away from the warm filling straight out of the oven is pure magic. I make this whenever the weather turns cold and we need a cozy dinner.

Why This Classic Works

I used to think casseroles were just a way to use up leftover canned soup, but making everything from scratch changes the whole dish. The fresh thyme and garlic completely transform the simple cream sauce into something special.

My biggest lesson was learning not to crowd the mushrooms in the pan. Searing them properly instead of steaming them adds a deep, savory flavor that makes this recipe stand out.

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Chicken Mushroom Casserole Ingredients

• 1 lb boneless skinless chicken breasts, diced
• 8 oz cremini mushrooms, sliced
• 1 medium yellow onion, diced
• 3 cloves garlic, minced
• 1 tbsp olive oil
• 1 cup chicken broth
• 1 cup heavy cream
• 1 tsp dried thyme
• 1/2 tsp salt
• 1/4 tsp black pepper
• 1 cup shredded mozzarella cheese
• 1/2 cup grated parmesan cheese

How To Make Chicken Mushroom Casserole

1. Sear the chicken: Heat olive oil in a large oven-safe skillet over medium-high heat, cooking the diced chicken until browned.
2. Cook the vegetables: Add the sliced mushrooms and diced onion to the skillet, cooking until the mushrooms are deeply browned and onions are soft.
3. Build the sauce: Stir in the minced garlic, dried thyme, salt, and pepper, cooking for one minute until fragrant.
4. Add the liquids: Pour in the chicken broth and heavy cream, bringing the mixture to a gentle simmer for five minutes to thicken.
5. Bake the casserole: Top evenly with mozzarella and parmesan cheese, then bake at 375°F for 15 minutes until bubbly and golden.

Recipe Tips

• Brown the mushrooms: Letting the mushrooms sit undisturbed for a few minutes ensures they get a deeply savory crust.
• Dice uniformly: Cut your chicken into equal bite-sized pieces so they cook evenly without drying out.
• Shred your own cheese: Pre-shredded cheese contains anti-caking agents that prevent it from melting smoothly into the rich cream sauce.

What To Serve With Chicken Mushroom Casserole

This rich dish pairs perfectly with a crisp green salad tossed in a sharp vinaigrette to cut through the heavy cream. You can also serve it over egg noodles or mashed potatoes to soak up every last drop of the savory sauce.

How To Store

Store leftovers in an airtight container in the fridge for up to four days. You can also freeze this casserole tightly wrapped for up to three months, thawing it overnight before reheating in the oven.

FAQs

Can I use chicken thighs instead?

Yes, boneless skinless chicken thighs work beautifully and stay very tender during baking. Just trim excess fat before dicing.

Can I make this ahead of time?

Absolutely. Assemble the entire casserole, let it cool completely, and keep it covered in the fridge for up to two days before baking.

What kind of mushrooms are best?

Cremini or baby bella mushrooms offer the best deep flavor, but standard white button mushrooms work well in a pinch.

Nutrition

• Calories: 410 kcal
• Total Fat: 28g
• Saturated Fat: 15g
• Cholesterol: 125mg
• Sodium: 650mg
• Total Carbohydrate: 8g
• Protein: 32g

Try More Recipes:

• Creamy Buffalo Chicken Casserole Recipe
• Buffalo Chicken Cauliflower Casserole Recipe
• Chicken Bacon Tater Tot Casserole Recipe