This Healthier Broccoli Chicken Casserole is creamy, comforting, and packed with wholesome ingredients. Made with lean chicken, hearty whole-wheat pasta, and a rich mushroom-cheddar sauce without any canned soup this lighter casserole is a satisfying meal the whole family will love.

Ingredients

8 oz uncooked pasta* (e.g., whole-wheat rotini)
1 large head of broccoli, cut into bite-sized florets (about 1 lb)
2 Tbsp butter or olive oil
1 small white onion, thinly sliced
8 oz baby bella (cremini) mushrooms, thinly sliced
4 cloves garlic, minced
3 Tbsp all-purpose flour
1 cup chicken or vegetable stock
1½ cups milk
1 tsp Dijon mustard
½ tsp fine sea salt
¼ tsp freshly cracked black pepper
2 cups (8 oz) shredded sharp cheddar cheese, divided
2 cups diced or shredded cooked chicken

*Use whole-wheat pasta for a fiber-rich option or gluten-free pasta if needed.

Instructions

Preheat Oven:
Heat your oven to 400°F (200°C).
Cook Pasta and Broccoli:
In a large pot of generously salted boiling water, cook pasta until just al dente. In the final minute of cooking, add the broccoli florets. Drain together and set aside.
Sauté Vegetables:
In a large sauté pan over medium-high heat, melt butter (or heat oil). Add the onion and cook for 3 minutes, stirring occasionally. Add mushrooms and garlic, and cook for another 5 minutes until the mushrooms are tender and browned.
Make the Sauce:
Sprinkle the flour over the sautéed mixture and stir to combine. Cook for 1 minute. Slowly pour in the stock, stirring constantly to break up clumps. Add milk, Dijon mustard, salt, and pepper. Bring the mixture to a simmer, then remove from heat and stir in 1 cup of cheddar cheese until melted.
Combine the Casserole:
In a 9×13-inch baking dish, combine the cooked pasta, broccoli, mushroom cheese sauce, and cooked chicken. Toss well to evenly combine and spread into an even layer.
Bake:
Bake uncovered for 15 minutes. Remove from the oven, sprinkle the remaining cheddar cheese on top, and return to the oven for 10 more minutes, or until the cheese is melted and bubbly.
Serve:
Serve warm, garnished with extra cracked black pepper or fresh herbs if desired.

Why You’ll Love This Recipe

Lighter comfort food: No canned soup, less saturated fat, but still creamy and indulgent.
Balanced meal: Full of protein, veggies, and whole grains in one dish.
Family-approved: Cheesy, hearty, and full of flavor that even picky eaters enjoy.
Easy to prep ahead: Great for meal prep or make-ahead dinners.

Tips

Cook pasta slightly under al dente since it will finish cooking in the oven.
Use freshly grated cheese for better melting and flavor.
Shred rotisserie chicken to save time.
Taste the sauce before baking to adjust seasoning if needed.

Variations and Substitutions

Use different veggies: Cauliflower, spinach, or bell peppers are great options.
Try other cheeses: Mozzarella, Monterey Jack, or Gruyère add variety.
Make it vegetarian: Skip the chicken and add more mushrooms or white beans.
Gluten-free: Use gluten-free pasta and flour.
Dairy-free: Swap cheese and milk with plant-based alternatives.

FAQs

Can I make this ahead of time?
Yes! Assemble the casserole, cover, and refrigerate for up to 24 hours before baking.

Can I freeze it?
Yes. Bake, cool, and freeze in portions. Reheat in the oven or microwave until warmed through.

What kind of chicken should I use?
Any cooked chicken—leftovers, poached breasts, or rotisserie—works well.

Can I skip the mushrooms?
Yes, just increase the onion or add another veggie like zucchini or spinach.

Serving

Serve hot with a side of fresh green salad, garlic bread, or roasted vegetables. It’s a perfect all-in-one meal for busy weeknights or cozy Sunday dinners.

Suggestions

Add crunch: Sprinkle with whole wheat breadcrumbs or crushed crackers before baking the final 10 minutes.
Herb it up: Mix in fresh thyme, parsley, or basil for extra flavor.
Meal prep: Divide into containers for easy grab-and-go lunches.
Kids’ version: Skip the mushrooms and use smaller pasta shapes like macaroni.