Cheesy Chicken Cauliflower Casserole
It doesn’t get any better than our chicken cauliflower casserole recipe. This tasty dish is a great potluck contribution, a BBQ side dish, and an easy-to-make weeknight meal. We’re big fans of the flavor and versatility!
The chicken is juicy, the cauliflower is tender and, let’s face it, it’s a winner because it contains melty cheese. It’s a crowd-pleaser and holds well overnight—if any leftovers exist!
When you’re making this recipe, keep in mind that warm milk incorporates easier than cold milk, which helps to make the mix of ingredients smooth instead of lumpy. You’ll see how easy it is to whisk it into the flour and butter!
Cheesy Chicken Cauliflower Casserole Recipe
- 2 lbs boneless, skinless chicken breasts, (approx. 3 large breasts)
- salt and pepper
- 1 head cauliflower, cut into 1" florets
- 2 Tbsp unsalted butter
- 1/2 yellow onion, diced
- 1 clove garlic, minced
- 2 Tbsp all-purpose flour
- 1 1/2 cups milk
- 1/2 tsp paprika
- 1/4 tsp dry mustard powder
- 1 tsp salt
- ground pepper, to taste
- 1 cup Parmesan cheese, grated
- Preheat oven to 350 degrees then coat a 2-qt casserole dish with cooking spray. Season chicken breasts lightly with salt and pepper then place in prepared casserole dish. Spritz top of chicken with cooking spray then bake 20–25 minutes or until just cooked through. Remove from oven, cover loosely with foil then let rest. Increase oven temperature to 425 degrees.
- Fill a large saucepan halfway with water then bring to a boil over high heat. Add cauliflower and a few pinches of salt. Cook cauliflower approximately 3 minutes until fork tender but still slightly crunchy. Drain and set aside.
- Return pot to stove then reduce heat to medium. Melt butter then add diced onion. Cook 3–4 minutes until onion is translucent then add garlic and cook 1 additional minute.
- Sprinkle in flour, stirring until dissolved. Cook approximately 1 minute, stirring frequently, then slowly whisk in milk. Bring mixture to a boil then add paprika, dry mustard, salt and pepper and stir to combine. Add Parmesan cheese then stir until melted and incorporated. Remove from heat then fold in chicken and cauliflower to fully coat with sauce.
- Coat casserole dish with cooking spray then add the chicken and cauliflower mixture. Sprinkle top with cheddar cheese and breadcrumbs then drizzle with melted butter. Sprinkle top with garlic salt then bake uncovered 10–15 minutes until the top is golden brown and the filling is hot and bubbly.