20-Minute Chicken & Broccoli Alfredo Bake (light)

Alfredo usually means a jar of heavy cream and a long guilt list. This bake keeps all the creamy comfort and skips most of the heavy stuff. Shredded rotisserie chicken — already cooked, which is what makes the 20 minutes honest — gets tossed with penne, tender broccoli, and a lightened alfredo sauce made with evaporated milk and Parmesan instead of heavy cream. Ten minutes in a hot oven melts a golden mozzarella top over everything, and it is on the table before anyone has time to ask what is for dinner twice.

Why you’ll love it

• 20 minutes, start to finish. Rotisserie chicken does the heavy lifting — no raw chicken to cook through, just shred and go.
• Lightened, not light-on-flavor. Evaporated milk plus plenty of Parmesan gives you a silky alfredo without heavy cream.
• ~40g protein per serving (estimated), from rotisserie chicken, mozzarella, and Parmesan.
• One baking dish. Everything lands in the same 9×13 — pasta, broccoli, chicken, sauce — then straight into the oven.

Ingredients

• 12 oz penne pasta
• 4 cups broccoli florets, about 1 large head
• 1 tbsp kosher salt, for the pasta water
• 3 cups shredded rotisserie chicken, about 1 large rotisserie chicken, skin removed
• 2 tbsp unsalted butter
• 3 cloves garlic, minced
• 1 (12 oz) can fat-free evaporated milk
• 1/4 cup low-sodium chicken broth
• 3/4 cup freshly grated Parmesan cheese, plus 2 tbsp for the top
• 1/4 tsp ground nutmeg
• 1/2 tsp kosher salt
• 1/2 tsp black pepper
• 1 1/2 cups shredded mozzarella cheese
• 2 tbsp chopped fresh parsley, for serving
• Cracked black pepper, for serving

Equipment

A 9×13-inch baking dish, a large pot for boiling pasta, a medium saucepan, and a whisk.

Instructions

1. Cook the pasta and broccoli (8 minutes). Bring a large pot of water to a rolling boil and salt it generously. Add the penne and cook for 6 minutes; stir in the broccoli florets and cook 2 minutes more, until the pasta is just shy of al dente and the broccoli is bright green and crisp-tender. Drain, reserving 1/4 cup of the pasta water. Heat the oven to 425°F.
2. Make the lightened alfredo (4 minutes). While the pasta cooks, melt the butter in a medium saucepan over medium heat. Add the garlic and cook 1 minute, until fragrant but not browned. Pour in the evaporated milk and chicken broth and warm until steaming — do not let it boil. Take the pan off the heat.
3. Whisk in the Parmesan (1 minute). Whisk the 3/4 cup Parmesan and the nutmeg into the warm milk until smooth and slightly thickened. Season with the salt and pepper. If the sauce looks too thick, whisk in a splash of the reserved pasta water.
4. Assemble the bake (2 minutes). In the baking dish, toss the drained pasta, broccoli, and shredded chicken with the alfredo sauce until everything is evenly coated. Spread into an even layer.
5. Top and bake (10 minutes). Shower the mozzarella and the remaining 2 tablespoons of Parmesan evenly over the top. Bake at 425°F for 8–10 minutes, until golden and bubbly around the edges. The chicken is already cooked — you are just heating everything through to steaming.
6. Rest and serve (2 minutes). Rest 2–3 minutes so the sauce sets and thickens slightly. Scatter with parsley and cracked black pepper and serve straight from the dish.

Doneness cues: The bake is done when the cheese is golden and the sauce bubbles at the edges of the dish; the chicken, being already cooked, just needs to be steaming hot (165°F) throughout. Do not overbake — the mozzarella goes from golden to rubbery past 10 minutes.

Nutrition note

Protein is estimated at about 40g per serving, calculated from USDA FoodData Central values for the listed ingredients — this is an estimate, not a lab analysis. Actual values vary by brand and preparation.

Substitutions and tips

• No rotisserie chicken? Use 1 1/2 lb cooked chicken breast (poached or leftover), shredded — but the total time becomes about 25 minutes.
• Other vegetables: cauliflower florets swap in 1:1; frozen broccoli works too (add it straight to the boiling pasta, no thawing needed).
• No evaporated milk? Use 1 1/2 cups whole milk whisked with 1 tablespoon cornstarch instead — same warming method, whisk well so it does not curdle.
• Make it spicier: add 1/2 teaspoon red pepper flakes with the garlic.
• Don’t boil the sauce. Evaporated milk can curdle at a hard boil; keep it at steaming and pull it off the heat before whisking in the Parmesan.

Storage and reheating

Refrigerate leftovers within 2 hours in an airtight container for up to 4 days. Reheat in the oven at 350°F, covered with foil, for 12–15 minutes, or microwave in 60-second bursts until steaming (165°F). A splash of milk when reheating loosens the sauce back up. Freezing is not recommended — the lightened sauce can separate when thawed.

Frequently asked questions

Is this really only 20 minutes? Yes — rotisserie chicken is the whole trick. Since the chicken is already cooked, you are only cooking pasta, whisking a sauce, and baking for 10 minutes. No raw chicken to bring to temperature.

Why evaporated milk instead of heavy cream? Fat-free evaporated milk is milk that’s had about half its water removed, so it’s creamy and slightly sweet without the heaviness of cream — and it doesn’t break when heated gently. The Parmesan carries the richness.

Can I use fresh Parmesan only? Please do, actually. Freshly grated Parmesan melts smoothly; the pre-shredded kind has anti-caking starch that can make the sauce grainy.

Can I assemble it ahead? Yes — assemble through step 4, cover, and refrigerate up to 24 hours. Add 3–4 minutes to the bake time when starting cold.

What should I serve with it? It’s a complete meal as is, but a simple green salad or garlic bread rounds it out nicely.

More creamy pasta bakes

For another creamy weeknight pasta, our 30-Minute One-Pot Taco Pasta is a reader favorite. Love sheet-pan dinners? 30-Minute Sheet Pan Chicken Parm & Veggies skips the frying. If you like takeout remakes, try our 25-Minute Honey Walnut Shrimp.