Chicken and Broccoli Alfredo Bake

By: Rachel TiemeyerPosted: 2/27/25Updated: 3/13/25

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Chicken and Broccoli Alfredo Bake is a decadent-tasting, wholesome, comfort food casserole that’s so easy to make. It’s high in protein and a little lighter than most Alfredo pastas. Plus it’s freezer-friendly, so double and freeze one for later while you’re at it.

Chicken broccoli alfredo bake being served from a glass baking dish.

Table of Contents

Things to Know About This Recipe

Lighter Comfort Food: This casserole is cheesy, creamy, flavor-packed and so comforting! Yet, you’ll use broth and whole milk in the Alfredo sauce instead of half and half or heavy whipping cream, making it a bit lighter than most.
Clean Ingredients: Our recipe has you make an easy Alfredo sauce from scratch, ensuring maximum freshness and flavor. At the same time, you’ll avoid the preservatives and additives in the store-bought kind.
Includes shortcuts, if you’re short on time.
Well-Tested: Friends, I tested this casserole seven times! I tried out various pans to get the timing correct, cooking your own chicken vs. using rotisserie chicken, testing it with homemade Alfredo sauce vs. jarred sauce, and testing it after freezing. I made all the mistakes so you don’t have to!
High Protein: With over 30 grams of a protein per serving, this casserole is high in protein while also delivering some fiber from the broccoli and whole grain pasta. Here’s more high protein meal prep ideas.
Freezer-friendly: Double and freeze one for later!

Ingredients

Here are the simple, real food ingredients you’ll need for this casserole…

Ingredient Notes

Whole grain penne pasta – I used Barilla Whole Grain Penne. You can make this casserole gluten-free (and higher in protein) by using chickpea penne pasta like Banza brand instead.
Broccoli florets – Cut these into bite-sized, uniform pieces. You can add up to another 1 cup if you want to “veg out”. I personally like the extra broccoli.
Rotisserie chicken – You’ll need about 1/2 pound of shredded meat or about 1/2 rotisserie chicken. I tested this recipe using raw chicken breasts that I diced, sautéed, and seasoned. It worked ok, but it took longer, was messier, and frankly didn’t have as much flavor as a rotisserie chicken.
Homemade Alfredo Sauce – I’ll share with you my lighter but still very flavorful homemade alfredo sauce in the recipe. However, if you’re short on time, you can substitute in one 15-ounce jar store-bought plain Alfredo Sauce + ⅓ cup milk. I tested the casserole with Raos Alfredo Sauce and it works just fine (although my homemade version tastes better!).

Testing Notes from Rachel’s Kitchen

This casserole went through 7 rounds of testing. Here are a few things I learned along the way that might be helpful to know:

I originally chopped up raw chicken breast and sautéed and seasoned it in a skillet to use in the casserole, which you can do if you want. But I didn’t like that it dirtied up another dish, took more time, and, frankly, it had far less flavor than the rotisserie chicken that I call for in the recipe.
I worked hard at creating an Alfredo sauce that is lighter but still as flavorful as any other. I found that the combo of whole milk and chicken broth, along with Parmesan cheese and seasoning, did the trick!
The last thing I had to figure out was how to get the ratios just right so you can swap in a 15 ounce jar of store-bought Alfredo sauce if you don’t have time to make the sauce yourself (which honestly just takes a few minutes, so I hope you try it!). I tested this casserole with Raos Alfredo plus an additional 1/3 cup milk for more moisture. While it was still good and works in a pinch, our family and Polly’s family definitely preferred the homemade sauce from the recipe.

How to Make Chicken and Broccoli Alfredo Bake

Here’s a brief visual overview of how to make this casserole. Find the full, printable recipe at the bottom of this post.

Cook the pasta and broccoli

Cook the pasta according to package instructions. Add the broccoli to the boiling water during the last 2 minutes. Drain and set aside.

Whole grain penne pasta and broccoli florets in a steamer basket.

Prepare the Alfredo Sauce

(Skip this step if using a jar from the store.) In a medium saucepan (or the same pot you cooked the pasta in) over medium heat, melt the butter until it begins to bubble gently. Using a whisk, stir in the flour and whisk for about 1 minute.

A hand whisking butter in a saucepan as it melts.

One hand dumping flour in a saucepan while the other hand is whisking the melted butter to make a roux.

Whisk in the chicken broth and the milk until smooth. Bring to a low simmer and cook for 1-2 minutes, until slightly thickened, whisking continually.

Chicken broth being whisked into a roux in a saucepan.

Milk being whisked into a saucepan while making homemade alfredo sauce.

Remove from the heat. Whisk in the grated Parmesan, salt, and pepper until well combined.

A bowl of grated parmesan cheese being dumped into a saucepan with a roux in it.

Combine Ingredients

In the pot you cooked the pasta in, combine the cooked pasta and broccoli, rotisserie chicken, Alfredo Sauce, garlic powder, Italian seasoning, and 1/2 cup shredded mozzarella (reserve the rest). Gently stir until evenly combined.

Ingredients for chicken broccoli alfredo bake in a pot waiting to be stirred.

Assemble the Casserole

Pour the mixture into the prepared 9×9-inch pan. Sprinkle remaining Parmesan cheese and mozzarella cheese evenly over the top.

A hand sprinkling grated parmesan cheese on a baking dish with ingredients for chicken broccoli alfredo bake in it.

Bake & Serve

Bake until the cheese is melted and bubbly. Optional: Turn on the broiler for 1 to 2 minutes, just until it starts to get a little golden on top (watch closely!). Top with fresh chopped parsley, if desired. Serve warm.

A serving of chicken broccoli alfredo bake being lifted out of a baking dish with a spoon.

Make It A Freezer Meal

This is a brilliant recipe to double and freeze. Here’s how:

To Freeze: Assemble the casserole (through Step 5), but do not bake. Cover tightly with several layers of plastic wrap and/or foil, label, and freeze.

To Prepare: Thaw about 24 hours in the refrigerator. Bake according to directions in Step 6.

An 8x8 baking dish covered with foil and labeled chicken broccoli alfredo bake.

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Chicken and Stuffing Casserole

All Freezer Casseroles

A spoon lifting a serving of chicken broccoli alfredo bake from a square pan.

Rachel Tiemeyer

As co-founder of Thriving Home, Rachel dreams about creating recipes (literally) and uses her husband, her 3 kids, and even the neighbors as guinea pigs several nights a week. She believes that good food has the power to bring families and friends closer together and continues to wake up excited about her job each day, even after 10+ years!

Chicken and Broccoli Alfredo Bake

Things to Know About This Recipe