Chicken Broccoli Alfredo Casserole

Picture a golden, bubbling casserole emerging from the oven—creamy Alfredo sauce clinging to ridged pasta, emerald broccoli tucked between tender bites of chicken, and a crown of melted mozzarella that stretches in silky strands.

Steam carries the buttery, garlicky aroma that says comfort is minutes away. This dish matters to me because it delivers big, restaurant-level flavor with pantry simplicity; it’s the kind of cozy, crowd-pleasing dinner that turns an ordinary evening into a small celebration.

On a week when after-school chaos collided with late meetings, this casserole saved dinner—and sanity—by being make-ahead friendly and reliably loved by everyone at the table.

It’s perfect for busy weeknights, potlucks, or laid-back Sunday suppers when you want a no-fuss main that still feels special. With tender chicken, bright broccoli, and a silky Parmesan sauce, it’s comfort with a fresh, balanced twist.

Ready? Let’s cook!

Why You’ll Love It

• Delivers cozy, restaurant-style Alfredo comfort in every bite
• Packs protein and veggies into a family-friendly bake
• Streamlines dinner with one skillet, one baking dish
• Makes ahead easily for weeknights or gatherings
• Reheats creamily with a splash of milk

Ingredients

• 12 ounces pasta shells or penne, uncooked — choose sturdy shapes that hold sauce well
• 3 cups broccoli florets, bite-sized — cut evenly for quick blanching
• 2 tablespoons unsalted butter — real butter for best flavor
• 1 tablespoon olive oil — helps brown chicken evenly
• 1 pound boneless skinless chicken breast, cut into 1-inch cubes — trim any silverskin
• 1 teaspoon kosher salt, divided — Diamond Crystal if possible for consistency
• 1/2 teaspoon black pepper, divided — freshly ground for brightness
• 3 cloves garlic, minced — mince fine to avoid burning
• 2 tablespoons all-purpose flour — for a smooth blond roux
• 2 cups heavy cream — yields a silky Alfredo
• 1 cup whole milk — balances richness
• 1/2 cup low-sodium chicken broth — keeps control over salt
• 1 cup freshly grated Parmesan cheese — grate fresh for melt and no grit
• 1/2 teaspoon Italian seasoning — a balanced herb blend
• 1/4 teaspoon crushed red pepper flakes, optional — add gentle heat
• 1 cup shredded mozzarella cheese — low-moisture for better browning
• 2 tablespoons fresh parsley, chopped — for fresh, bright finish

Step-by-Step Method

Preheat & Prep

Preheat the oven to 375°F. Grease a 9×13-inch baking dish. Set out a large pot, colander, skillet, whisk, and measuring tools. Chop broccoli into bite-sized florets and cube chicken into 1-inch pieces.

Mince garlic and grate cheeses. This mise en place speeds cooking and guarantees the sauce and pasta come together smoothly without overcooking anything.

Boil Pasta & Blanch Broccoli

Bring a large pot of well-salted water to a boil. Add pasta and cook 2 minutes shy of package directions to keep it al dente after baking. In the last 2 minutes, add broccoli florets to blanch. Drain both together in a colander and set aside. Don’t rinse; the residual heat helps finish cooking.

Sear the Chicken

Heat olive oil and 1 tablespoon butter in a large skillet over medium-high heat. Pat chicken dry, then season with 1/2 teaspoon salt and 1/4 teaspoon pepper. Sear, stirring occasionally, until cooked through and lightly golden, 5 to 6 minutes. Transfer chicken to a plate, leaving browned bits in the skillet for flavor.

Sauté Garlic & Make Roux

Reduce heat to medium. Add remaining 1 tablespoon butter to the skillet. Stir in minced garlic and sauté for 30 seconds until fragrant. Sprinkle in flour and whisk continuously for 1 minute to form a blond roux. This step removes raw flour taste and builds body for a smooth, velvety Alfredo sauce.

Whisk in Liquids & Simmer

Slowly whisk in heavy cream, milk, and chicken broth, scraping up any fond. Keep whisking until smooth. Bring to a gentle simmer and cook 3 to 5 minutes, stirring, until slightly thickened and able to lightly coat a spoon. Adjust heat to avoid boiling, which can cause separation or graininess.

Finish the Alfredo Sauce

Stir in Parmesan, Italian seasoning, remaining 1/2 teaspoon salt, remaining 1/4 teaspoon pepper, and crushed red pepper flakes if using. Mix until the cheese melts and the sauce turns silky. Taste and adjust seasoning. If too thick, whisk in a splash more milk; if too thin, simmer briefly to reduce gently.

Combine & Toss in Dish

Add pasta, blanched broccoli, and seared chicken to the greased baking dish. Pour the Alfredo sauce over the top. Toss gently with a wooden spoon to coat everything evenly and distribute chicken and broccoli throughout. Smooth the surface so the topping melts and browns consistently during baking.

Top Generously

Sprinkle shredded mozzarella evenly over the casserole. Add a little extra grated Parmesan for sharper flavor and better browning. Guarantee coverage reaches the corners to prevent dried pasta edges. For a touch of heat and color, add a pinch of crushed red pepper or black pepper over the cheese.

Bake Until Bubbly

Place the dish on the center rack and bake uncovered for 18 to 22 minutes. Look for bubbling edges and lightly browned, melted cheese on top. If browning too quickly, tent loosely with foil. Avoid overbaking to keep the pasta tender and the sauce creamy rather than dry or separated.

Rest, Garnish & Serve

Remove from the oven and let rest 5 minutes to set the sauce for cleaner scoops. Sprinkle with chopped fresh parsley for color and freshness. Serve warm, adding extra Parmesan at the table. For leftovers, reheat gently with a splash of milk, covered, to revive the sauce’s creaminess.

Ingredient Swaps

• Pasta: Use any short pasta (rotini, rigatoni, ziti). For gluten-free, swap with GF pasta; for low-carb, use steamed cauliflower or zucchini noodles (skip baking time slightly).
• Dairy: Replace half the heavy cream with evaporated milk or whole milk for lighter; use lactose-free cream/milk and Parmesan. For dairy-free, use unsweetened cashew cream or coconut milk and a melty vegan mozzarella/parmesan.
• Chicken: Swap with rotisserie chicken, turkey, Italian chicken sausage, or canned chicken for budget ease; for vegetarian, use white beans or chickpeas, or sautéed mushrooms.
• Broccoli: Substitute with cauliflower, peas, spinach, or mixed frozen vegetables (no need to pre-blanch; thaw and pat dry).
• Broth/Seasoning: Use vegetable broth for vegetarian; if Italian seasoning isn’t on hand, use a mix of dried basil, oregano, and thyme.

You Must Know

• Doneness • If the sauce looks thin in the skillet, reduce heat and keep stirring 2–3 minutes until it coats the back of a spoon and a finger swipe leaves a clean line; this prevents a watery casserole after 18–22 minutes in the oven.
• Troubleshoot • When the Alfredo turns grainy after adding Parmesan, pull the pan off heat for 30–60 seconds and stir in 1–2 tablespoons warm milk; cheese seized from too-high heat, and gentle dilution restores smoothness.
• Flavor Boost • For deeper savory notes, deglaze the browned chicken bits with 2–3 tablespoons low-sodium broth until the pan is nearly dry; those fond sugars add a roasted flavor you’ll taste in every bite.
• Swap • To lighten, use 1 cup heavy cream + 1 cup evaporated milk and 6 ounces pasta (half); the sauce-to-pasta ratio stays creamy while trimming richness and calories.
• Scale • For 8–10 servings, increase all ingredients by 50% and use a 12×16-inch dish; extend oven time by 5–8 minutes, pulling when the center hits 165°F and the top is spotty golden with bubbling at the edges.

Serving Tips

• Serve with garlic bread or warm focaccia to soak up extra sauce.
• Add a crisp Caesar or arugula-lemon salad for freshness.
• Garnish generously with parsley, cracked pepper, and extra Parmesan at the table.
• Pair with chilled Pinot Grigio, Sauvignon Blanc, or sparkling water with lemon.
• Plate in warm bowls; top with red pepper flakes for heat.

Storage & Make-Ahead

Refrigerate tightly covered within 2 hours; keeps 3–4 days.

Reheat gently, covered, with a splash of milk to loosen the sauce.

Assemble up to 24 hours ahead; bake covered 15 minutes, then uncover until bubbly.

Freezes well up to 2 months; thaw overnight and reheat covered, adding milk if needed.

Reheating

Reheat gently: add splash of milk, cover.

Microwave 50% power, stirring intervals.

Oven 325°F, covered, 15–20 minutes until warmed.

Stovetop low heat, covered, stir often.

Avoid boiling to prevent separating, drying.

Tiktok Weeknight Staple

Sometimes I need a crowd-pleasing dinner that’s as scroll-stopping as it’s simple, and this Chicken Broccoli Alfredo Casserole delivers. It hits all the TikTok weeknight marks: minimal chopping, pantry-friendly ingredients, and that irresistible cheese pull.

I par-cook shells with broccoli, sear juicy chicken, then whisk a fast, glossy Alfredo—cream, milk, and Parmesan—until it coats the spoon.

Here’s the vibe: steam curls up, garlic smells buttery, mozzarella blisters, and the top freckles golden. I toss everything in a 9×13, shower with more cheese, and bake until bubbly.

Want short-cut magic? Use rotisserie chicken. Crave heat? Add a pinch of red pepper flakes. Film the reveal, fork twirl and all—silky sauce, tender pasta, bright broccoli—then serve before the comments roll in.

Final Thoughts

Ready to dig in? Give this creamy Chicken Broccoli Alfredo Casserole a try, and feel free to make it your own—swap the pasta shape, add extra veggies, or spice it up to taste!

Frequently Asked Questions

Can I Make It Gluten-Free Without Sacrificing Texture?

Yes—you can. Use sturdy gluten-free penne, a 1:1 GF flour blend for the roux, and verify broth’s GF. Whisk till glossy, bake until bubbling, and you’ll keep velvety sauce, springy pasta, and golden, melty top.

What’s the Best Way to Freeze Unbaked Casserole?

Freeze it unbaked after cooling ingredients: assemble, use slightly undercooked pasta, skip parsley, wrap tightly in plastic and foil, label, and freeze flat. I bake from frozen at 375°F, covered 30 minutes, then uncovered until bubbly.

How Do I Prevent a Grainy Alfredo Sauce?

Use freshly grated Parmesan, not pre-shredded. I whisk a blond roux, then slowly add warm cream and milk off heat. Keep it below a simmer, season last, and avoid lemony acids. The sauce stays silky.

Can I Cook This Entirely on the Stovetop?

Yes—you can. I’d simmer pasta and broccoli together, sear chicken, then make the creamy sauce. Toss everything in the skillet, melt mozzarella under a lid, and finish with parsley. It’ll smell buttery, taste silky, and satisfy.

Which Pasta Shapes Hold the Sauce Best?

Rigatoni, orecchiette, shells, and penne grip creamy sauce best. I love how ridges catch silky bites. If you crave extra cling, cook al dente, reserve starchy water, and toss vigorously until glossy, velvety, and well-coated.