Baked Chicken Alfredo Pasta Casserole

Prep Time	Cook Time	Total Time
20 min	35 min	55 min

How to Make Baked Chicken Alfredo Pasta Casserole

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Preheat oven and prep baking dish

Preheat your oven to 375°F and lightly spray a 9x13-inch baking dish with olive oil spray.
Cook the pasta

Bring a large pot of salted water to a boil and cook the penne until just shy of al dente.
Drain the pasta, toss it lightly with a little olive oil if you like, and set aside.

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Prepare the chicken

If using cooked chicken, shred or dice it into bite-size pieces and keep it ready near the stove.
If using raw chicken breast, cut it into small 1 inch pieces so it cooks evenly in the casserole.
Make the garlic cream sauce

Melt the butter in a large saucepan over medium heat, then add the minced garlic and cook until fragrant.
Whisk in the flour and cook for 1 to 2 minutes, stirring constantly, until the mixture smells nutty.
Slowly whisk in the chicken broth, a splash at a time at first, until smooth, then add the heavy cream.
Stir in the Parmesan, mozzarella, salt, pepper, and dried oregano and simmer until the sauce is thick and creamy.
Combine pasta, chicken, and sauce

In a large bowl, gently combine the cooked pasta, shredded chicken, and most of the sauce, reserving about 1 cup.
If using raw chicken, stir the pieces into the hot sauce first so they warm slightly before meeting the pasta.
Toss until everything is evenly coated, then spread the mixture into the prepared baking dish.

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Top with cheese and bake

Pour the reserved sauce over the top and sprinkle with the remaining mozzarella plus extra, if you like it extra cheesy.
If using cooked chicken, bake for 18 to 22 minutes, until the casserole is bubbling and the top is lightly browned.
If using raw chicken, cover the dish with foil and bake for 30 to 35 minutes, until the chicken reaches 165°F.
If you used foil, remove it for the last 5 to 10 minutes so the cheese can brown nicely.
Rest and serve

Let the casserole rest for at least 10 minutes after baking so the sauce thickens slightly and slices more neatly.
Garnish with extra Parmesan or a pinch of dried oregano, then scoop into bowls and serve warm.

Substitutions

Cooked shredded chicken -> rotisserie, canned, or raw chicken breast: You can swap the cooked chicken for shredded rotisserie chicken, which adds extra flavor and keeps the meat very tender. Well-drained canned chicken also works and gives a softer texture, which blends nicely into the creamy sauce. If using raw chicken breast, use about 1 pound and bake covered 30 to 35 minutes so it cooks safely.
Heavy cream -> half-and-half plus cream cheese: For a slightly lighter sauce, use 3/4 cup half-and-half plus 1/4 cup softened cream cheese instead of heavy cream. This keeps the sauce thick and rich, with a slight tang that balances the Parmesan and mozzarella.
Penne pasta -> rigatoni or rotini: If you do not have penne, rigatoni or rotini hold the sauce beautifully and bake without getting mushy. Their ridges grab the creamy Alfredo, so every bite tastes saucy and satisfying.

Tips

Salt your pasta water well: Season the cooking water generously, about 1 to 2 tablespoons kosher salt per large pot, so the pasta tastes flavorful.
Grate your own cheese: Pre-grated cheese often contains anti-caking agents that prevent smooth melting and can make the sauce grainy. Freshly grated Parmesan and mozzarella melt silkier and give the casserole better stretch and flavor.
Watch the roux closely: Do not let the flour and butter brown too much, or the sauce may taste heavy rather than creamy. Stop cooking as soon as it smells nutty and loses the raw flour scent.
Let the casserole rest: The sauce thickens as it cools slightly, so resting time keeps the servings neat instead of soupy. This also protects your mouth from molten cheese burns.
Broil briefly for extra color: For a deeper golden top, broil the casserole on the middle rack 1 to 3 minutes, watching constantly. Pull it out as soon as the cheese has brown spots and bubbling edges.

Energy	588	kcal
Protein	33	g
Total Fat	30	g
Carbohydrates	49	g
Dietary Fiber	4	g

FAQ

Can I make this baked chicken Alfredo pasta casserole ahead of time?: Yes, assemble the casserole completely, cover tightly, and refrigerate up to 24 hours before baking. Bake straight from the fridge, adding about 10 extra minutes, and check that everything is hot and bubbling.
How do I prevent the sauce from turning grainy?: Always add cheese off the heat or over very low heat, and whisk constantly as it melts. Also avoid boiling the sauce after adding cheese, since high heat can cause separation and a rough texture.
Can I freeze leftover chicken Alfredo casserole?: Yes, cool the baked casserole completely, then portion into airtight containers and freeze up to 2 months. Reheat covered in a 350°F oven with a splash of milk or broth until hot and creamy again.
What if my casserole looks dry after baking?: If the top looks dry, stir in a few tablespoons of hot chicken broth or warm cream around the edges. Cover with foil and return to the oven for 5 to 10 minutes so the sauce loosens slightly.

Reviews

Noah Miller, Cedar Rapids, Iowa: Really nice recipe, but note that "2½ chicken broth" misses the unit. It guessed it meant 2½ cups and it turned out fine. — 4 ★

Eunice: Thanks for pointing out the missing unit, Noah—we’ll double-check and update that!