This chicken casserole is a hearty, practical dinner with roasted chicken, tender broccoli, cauliflower rice, a savory rosemary-sage coconut milk sauce, and crisp bacon. It’s flavorful, filling, and ideal for a comforting weeknight meal.

If you like casseroles that feel substantial without relying on pasta or a heavy cheese sauce, this one is a great option. Roasting the chicken and broccoli first gives you better texture and more concentrated flavor before everything goes into the casserole dish.

The creamy sauce ties it all together. Coconut milk adds richness, while mustard, garlic, nutritional yeast, rosemary, and sage build plenty of savory flavor. Once the cauliflower rice is stirred in and the casserole finishes baking, you get a warm, satisfying dinner with bacon scattered over the top for a smoky, crisp finish.

Ingredients

You don’t need a complicated ingredient list to create plenty of flavor here. A few fresh herbs and pantry ingredients turn the chicken, broccoli, and cauliflower rice into a complete casserole.

Chicken breast: Cut into small pieces so it roasts quickly and mixes evenly throughout the casserole.
Broccoli florets: Roasting them separately helps preserve their texture instead of letting them become overly soft in the sauce.
Avocado oil: Coats the chicken and broccoli before roasting and encourages even cooking.
Cauliflower rice: Adds body to the casserole while soaking up some of the creamy sauce.
Chicken broth: Provides the liquid foundation and savory flavor for the sauce.
Full-fat coconut milk: Gives the sauce its smooth, creamy consistency without making it excessively heavy.
Ghee: Used to soften the onion and garlic while adding richness to the sauce.
Onion and garlic: Create the aromatic base that gives the casserole deeper savory flavor.
Tapioca flour: Thickens the broth and coconut milk into a sauce that coats the chicken and vegetables.
Nutritional yeast: Adds another layer of savory flavor to the creamy mixture.
Spicy brown mustard: Gives the sauce a gentle tang that balances its richness.
Fresh rosemary and sage: Bring a fragrant, savory herb flavor that works especially well with chicken.
Bacon: Cooked until crisp and crumbled over the casserole for a salty, smoky finishing layer.
Salt and black pepper: Used to season each component and bring the other flavors together.

Cooking Steps

STEP 1: Preheat your oven to 425°F. Spread the bite-size chicken pieces on one baking sheet and the broccoli florets on another. Coat each with half of the avocado oil and season lightly with salt and pepper.

STEP 2: Roast the chicken for about 20 to 25 minutes, turning the pieces halfway through, until fully cooked. Roast the broccoli alongside it for approximately 15 to 20 minutes, stirring once, until tender but still holding its shape. Lower the oven temperature to 400°F when both are finished.

STEP 3: While the chicken and broccoli roast, cook the bacon in a large skillet until crisp. Transfer it to a paper towel-lined plate so excess fat can drain, then crumble it once it is cool enough to handle.

STEP 4: Melt the ghee in a medium saucepan over medium heat. Add the chopped onion and cook until softened and translucent. Stir in the minced garlic and cook briefly until fragrant, adjusting the heat as necessary so the garlic does not brown too quickly.

STEP 5: Whisk the tapioca flour into the chicken broth until no visible lumps remain. Slowly add the mixture to the saucepan, followed by the coconut milk, mustard, and nutritional yeast. Bring everything to a boil while whisking, then reduce the heat and simmer for about 1 minute until noticeably thickened.

STEP 6: Stir the rosemary, sage, salt, and pepper into the sauce. Add the cauliflower rice and mix until evenly coated. Let it begin to soften in the warm sauce, then remove the saucepan from the heat.

STEP 7: Add the roasted chicken and broccoli to a casserole dish. Pour in the cauliflower rice and creamy herb sauce, then gently stir everything together. Scatter the crumbled bacon evenly across the top.

STEP 8: Bake uncovered at 400°F for about 20 minutes. The casserole is ready when it is hot throughout, the sauce has settled around the chicken and vegetables, and the cauliflower rice is tender. Serve while warm.

Serving Ideas for Chicken Casserole

Because this casserole already contains chicken and plenty of vegetables, it works well as a complete meal on its own. If you want to round out the dinner, keep the sides relatively simple.

Simple green salad: A crisp salad with a tangy dressing offers a fresh contrast to the creamy sauce and smoky bacon.
Roasted vegetables: Carrots, Brussels sprouts, or green beans can turn the casserole into an even more substantial dinner.
Warm bread: A simple slice of bread or a dinner roll is useful for picking up any extra herb sauce left on the plate.

Can I prepare the casserole ahead of time?

Yes. You can roast the chicken and broccoli, cook the bacon, and prepare the sauce in advance. Assemble everything in the casserole dish, cover, and refrigerate. Add the bacon before baking if you want it to retain more of its crisp texture.

If you bake the casserole straight from the refrigerator, it may need a little additional oven time to become hot all the way through.

Why roast the chicken and broccoli first?

Roasting gives both ingredients better texture before they are combined with the sauce. The chicken cooks evenly without having to simmer in the casserole, while the broccoli becomes tender without absorbing too much liquid.

It also lets you control the doneness of each ingredient separately before the final bake.

Can I use frozen broccoli?

Fresh broccoli works particularly well because it can be roasted until tender without releasing much excess moisture. Frozen broccoli naturally contains more water and may make the casserole softer.

If frozen broccoli is what you have, thaw it thoroughly and remove as much moisture as possible before using it.

How do I know when the chicken is cooked?

The chicken should be completely cooked before it is added to the casserole. For the most reliable check, the thickest pieces should reach an internal temperature of 165°F.

Cutting the chicken into similarly sized pieces before roasting also helps everything finish at roughly the same time.

What keeps the sauce from becoming too thin?

Tapioca flour is whisked into the broth before the liquid goes into the saucepan. Bringing that mixture to a boil and then briefly simmering it allows the sauce to thicken.

The cauliflower rice will also absorb some moisture during the final bake, giving the finished casserole a more cohesive texture.

Helpful Tips

Keep the pieces similar in size. Uniform chicken pieces and broccoli florets cook more evenly and are easier to distribute throughout the casserole.
Whisk the thickener thoroughly. Blend the tapioca flour into the cool broth before adding it to the hot pan to minimize lumps.
Don’t overcook the broccoli initially. Remember that it will return to the oven during the final 20-minute bake, so it only needs to become tender during roasting.

How to Store & Reheat

Allow leftovers to cool before transferring them to a tightly covered container. Refrigerate the casserole for up to 3 to 4 days. Keeping it properly covered helps prevent the chicken from drying out and keeps refrigerator odors from affecting the sauce.

For individual portions, reheating in the microwave is the quickest method. Cover loosely and heat in short intervals until the chicken and sauce are thoroughly hot. If the mixture seems thicker after refrigeration, stirring it partway through reheating will help redistribute the sauce.

For a larger amount, place the casserole in an oven-safe dish, cover it to reduce moisture loss, and warm at about 350°F until heated through. You can uncover it near the end if you prefer the top slightly drier.

The casserole can also be frozen for roughly 2 to 3 months in a freezer-safe container. Keep in mind that the vegetables and coconut milk-based sauce may be somewhat softer after freezing and thawing. For the most consistent texture, refrigerating and reheating leftovers within a few days is the better option.

With its roasted chicken, broccoli, creamy herb sauce, cauliflower rice, and crisp bacon topping, this is the kind of casserole that works particularly well when you want one warm dish to cover dinner. The separate roasting steps take a little extra effort, but they give you much better control over the final texture and make every part of the casserole feel distinct instead of simply simmered together.