When the craving for comfort food strikes, few dishes hit the spot like a warm, bubbling casserole. Our Creamy Chicken and Spinach Casserole brings together the cozy richness of tender chicken, the nutritious earthiness of spinach, and a creamy, cheesy sauce that ties everything together in a heartwarming embrace. This recipe is the perfect balance of indulgent and wholesome — ideal for weeknight dinners, meal prep, or feeding a crowd.

Whether you’re a busy parent, a meal-prepping student, or just a food lover on the hunt for your next favorite, this easy chicken casserole will win your heart with every spoonful.

🛒 Ingredients

2 tablespoons olive oil
1 medium onion, diced
3 garlic cloves, minced
2 cups cooked chicken breast, shredded or chopped
3 cups fresh spinach (or 1½ cups frozen, thawed and drained)
1 teaspoon salt
½ teaspoon black pepper
½ teaspoon dried thyme
¼ teaspoon red pepper flakes (optional)
2 tablespoons all-purpose flour
1½ cups milk (whole or 2%)
½ cup chicken broth
½ cup sour cream
1½ cups shredded mozzarella cheese
½ cup grated Parmesan cheese
1 cup cooked pasta or rice (optional for base layer)
½ cup breadcrumbs (optional topping)
2 tablespoons butter (for breadcrumb topping)

🍳 Instructions

Preheat your oven to 375°F (190°C). Lightly grease a 9×9 or 9×13-inch baking dish, depending on how thick you want your casserole.
Sauté the aromatics: Heat olive oil in a skillet over medium heat. Add diced onion and cook until soft and translucent, about 4–5 minutes. Stir in garlic and cook another minute.
Add spinach: Toss in the fresh spinach and cook until wilted (2–3 minutes). If using frozen spinach, make sure it’s well-drained before adding.
Season and stir: Add salt, black pepper, thyme, and red pepper flakes (if using). Mix well.
Make the roux: Sprinkle in the flour and stir to coat everything. Let cook for 1 minute to eliminate the raw flour taste.
Create the creamy sauce: Slowly pour in the milk and chicken broth, whisking to prevent lumps. Bring to a simmer and cook until thickened, about 3–4 minutes.
Add sour cream and cheese: Stir in the sour cream, mozzarella, and half of the Parmesan. Mix until the cheese is melted and the sauce is silky.
Fold in chicken: Add the cooked chicken and stir to coat with the creamy sauce.
Layer (optional): If using cooked pasta or rice, layer it in the bottom of the baking dish first. Then pour the creamy chicken and spinach mixture over the top.
Topping time: Mix breadcrumbs with melted butter and remaining Parmesan cheese. Sprinkle evenly over the casserole.
Bake for 20–25 minutes, or until the top is golden and bubbly.
Cool and serve: Let the casserole sit for 5–10 minutes before serving to allow it to set.

💡 Pro Tips & Variations

Make it low-carb: Skip the pasta or rice and enjoy it as-is — still hearty and filling!
Add more veggies: Mushrooms, peas, or bell peppers add both texture and nutrition.
Spice it up: Mix in a dash of cayenne or diced jalapeños for a kick.
Make it ahead: Prepare the casserole up to 2 days in advance and refrigerate. Bake when ready to serve.
Freeze it: Assemble but don’t bake. Wrap tightly and freeze for up to 2 months. Bake from frozen at 350°F for about 45 minutes.

🍽️ Serving Suggestions

This creamy casserole pairs beautifully with:

Garlic bread or crusty baguette slices
A fresh green salad with vinaigrette
Roasted vegetables like broccoli or carrots
A chilled glass of white wine like Chardonnay

📚 Fun Fact

Casseroles became widely popular in America during the 1950s as a symbol of easy, family-style meals. They’ve evolved over time, and today’s casseroles — like this creamy chicken and spinach delight — are beloved for their versatility, comfort, and ability to feed a hungry crowd without breaking the bank.