This Cheesy Sour Cream Chicken Casserole is a warm, satisfying dish that’s perfect for any night of the week. With tender chicken breasts smothered in a rich sour cream and Parmesan sauce, topped with melty mozzarella, each bite is loaded with creamy, cheesy goodness. Serve this casserole with roasted veggies or a fresh green salad to round out a deliciously comforting meal.

Why You’ll Love This Recipe:

Creamy and Cheesy: The combination of mozzarella and Parmesan with sour cream creates a creamy, gooey texture that’s simply irresistible.
Simple Ingredients: Made with pantry staples, this dish doesn’t require any special ingredients, yet the flavor is rich and satisfying.
Family-Friendly: Kids and adults alike will enjoy this comforting casserole, which pairs well with a variety of sides.
Make-Ahead Friendly: You can prep this dish in advance and pop it in the oven when you’re ready, making it convenient for busy days.

Key Ingredients:

Each ingredient in this casserole has a purpose, and a few small tips can make this dish even better!

Chicken Breasts: Use boneless, skinless chicken breasts for the best results. If they’re particularly thick, consider slicing them in half to ensure they cook evenly.
Mozzarella Cheese: This cheese melts smoothly over the chicken, creating a gooey layer. If you prefer a sharper flavor, substitute with provolone.
Parmesan Cheese: Freshly grated Parmesan is ideal as it melts better and has a more robust flavor. It also gives the casserole a nice golden crust.
Sour Cream: Full-fat sour cream works best for a rich, creamy sauce. If you prefer a lighter version, you can use low-fat sour cream, but avoid fat-free as it can make the sauce too watery.
Cornstarch: Cornstarch helps to thicken the sauce slightly, ensuring it stays creamy without being too runny.
Herbs and Seasonings: Oregano and garlic powder add a subtle, earthy flavor. You can swap in Italian seasoning for a different herbal note if you prefer.

Complete list of ingredients with quantities and instructions is located in the recipe card below

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Instructions:

Step 1: Preheat the Oven

Set the Temperature: Preheat your oven to 375°F (190°C). This will ensure the chicken cooks evenly while the cheese becomes golden and bubbly.
Prepare the Baking Dish: Lightly grease a 9×13-inch baking dish with oil. This will help prevent the casserole from sticking and make cleanup easier.

Step 2: Prepare the Chicken

Place Chicken in the Dish: Lay the chicken breasts flat in the baking dish.
Optional Seasoning: If desired, sprinkle a pinch of salt and pepper over each chicken breast to enhance its flavor.

Step 3: Make the Sour Cream Mixture

Combine Ingredients: In a mixing bowl, blend the following until smooth:
1 cup sour cream
1/2 cup finely shredded Parmesan cheese
1/2 teaspoon salt
1/4 teaspoon pepper
1 teaspoon dried oregano
1/2 teaspoon garlic powder
1 tablespoon cornstarch (to slightly thicken the sauce)
Mix Thoroughly: Stir until all ingredients are well incorporated for a creamy, flavorful sauce.

Step 4: Assemble the Casserole

Add Mozzarella Cheese: Place a slice of mozzarella cheese on top of each chicken breast. This will create a gooey, melty layer.
Add Sour Cream Mixture: Spoon the sour cream mixture over the chicken breasts, spreading it evenly to ensure each piece is coated.
Top with Parmesan: Sprinkle the remaining Parmesan cheese over the casserole. This will create a cheesy, golden crust as it bakes.

Step 5: Bake to Perfection

Bake: Place the baking dish in the preheated oven and bake for about 1 hour.
Check for Doneness: The casserole is done when the chicken reaches an internal temperature of 165°F (74°C) and the cheese is golden and bubbly. If the cheese begins to brown too quickly, cover the dish with foil.

Step 6: Let It Rest

Resting Period: Once done, remove the casserole from the oven and let it sit for a few minutes. This allows the sauce to thicken slightly and the flavors to meld.

Step 7: Garnish and Serve

Garnish: Sprinkle fresh parsley or chives over the casserole for a pop of color and added flavor.
Serve Hot: Serve the casserole warm alongside roasted vegetables, a crisp salad, or fluffy rice for a complete and comforting meal.

Serving Suggestions:

This cheesy sour cream chicken casserole pairs beautifully with a variety of sides for a complete meal:

Roasted Vegetables: Serve alongside roasted broccoli, carrots, or Brussels sprouts to balance out the creamy richness of the casserole.
Fluffy Rice or Mashed Potatoes: Either option makes a perfect base to soak up the delicious sauce.
Crisp Side Salad: A fresh green salad with a light vinaigrette helps cut through the richness of the casserole and adds a refreshing contrast.
Garlic Bread: For an indulgent touch, serve with warm garlic bread to mop up any extra sauce.

Storage and Meal Prep Tips:

This casserole is easy to make ahead and holds up well for leftovers, making it ideal for meal prep.

Refrigeration: Store any leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in the oven at 350°F (175°C) until warmed through, or microwave individual portions for convenience.
Freezing: You can freeze the casserole either before or after baking. To freeze before baking, assemble the dish, cover it tightly with foil, and freeze for up to 2 months. When ready to bake, thaw overnight in the fridge, then bake as directed. To freeze after baking, let the casserole cool completely, then wrap tightly and freeze. Reheat in the oven until hot.
Make-Ahead Tip: Assemble the casserole up to 1 day in advance and refrigerate, then bake when you’re ready to serve. This is a great time-saver for busy weeknights or when preparing for guests.

Recipe Variations:

This casserole is easy to adapt to suit different tastes and dietary needs. Here are some fun variations to try:

Add Spinach or Mushrooms: Layer in fresh spinach or sliced mushrooms between the chicken and cheese for added nutrients and flavor.
Herb Substitutions: Swap oregano for thyme, rosemary, or Italian seasoning for a different flavor profile.
Cheese Swap: For extra flavor, use provolone, Swiss, or a blend of cheeses instead of mozzarella.
Spicy Kick: Add a pinch of red pepper flakes to the sour cream mixture for a hint of heat.

Conclusion:

This cheesy sour cream chicken casserole is the ultimate comfort food—perfect for a cozy dinner at home or a special family meal. With its rich flavors, creamy sauce, and golden, cheesy top, it’s sure to be a crowd-pleaser. Whether you’re a fan of easy weeknight meals or looking for a hearty dish to impress guests, this casserole delivers on all fronts. Give it a try and enjoy every delicious, cheesy bite!