Creamy Baked Chicken Spaghetti

Baked chicken spaghetti turns a few pantry staples into a creamy, cheesy casserole that feels like a weeknight win. It is the sort of dinner that leaves you with a clean plate and a happy family, without pulling out every pot in the kitchen.

The pasta soaks up a rich sauce made from cream of chicken soup, sour cream, and a good amount of cheese, while shredded rotisserie chicken keeps the prep fast. You get all the comfort of a slow-simmered meal in under an hour.

Why This Baked Spaghetti Works

I love a casserole that does not ask for a sinkful of dishes. The whole thing comes together in one big bowl, one baking dish, and about 15 minutes of hands-on time. Then the oven takes over.

The mix of melted cheddar and mozzarella gives you that stretchy pull and a crisp top layer. The sour cream keeps the sauce from feeling heavy, and the chicken makes it filling enough to stand on its own with a simple salad on the side.

Ingredients

• 12 oz spaghetti – cooked and drained, a minute shy of al dente
• 2 cups shredded cooked chicken – rotisserie chicken works perfectly here
• 1 can (10.5 oz) cream of chicken soup
• 1 cup sour cream – full fat gives the richest texture
• 1/2 cup whole milk
• 1/2 cup diced yellow onion
• 2 cloves garlic – minced
• 1 tbsp unsalted butter
• 1 tsp garlic powder
• 1/2 tsp black pepper
• 1/4 tsp salt – plus more for the pasta water
• 2 cups shredded sharp cheddar cheese – divided
• 1 cup shredded low-moisture mozzarella cheese – divided

Variations / Substitutions

• Swap the protein – Leftover turkey, canned chicken, or even browned ground beef all work nicely.
• Change the cheese – An all-cheddar version gets extra sharp; pepper jack adds a little heat.
• Use cream of mushroom – It brings a slightly earthier flavor that still pairs well with chicken.
• Go dairy-free – Pick a dairy-free cream soup, sour cream alternative, and meltable vegan cheese.
• Add vegetables – Stir in 1 cup of thawed frozen peas or chopped fresh spinach before baking for a little color.

If you prefer a tomato-based starter, try our Baked Ziti with Sausage.

How to Make Baked Chicken Spaghetti

Step 1: Sauté the Aromatics

Preheat your oven to 350°F (180°C). In a small skillet, melt the 1 tbsp butter over medium heat. Add the 1/2 cup diced onion and cook, stirring occasionally, for 4 to 5 minutes, until the pieces turn translucent and soft. Toss in the minced garlic and let it sizzle for about 30 seconds, just until fragrant; then pull the pan off the heat.

In a large mixing bowl, whisk together the can of cream of chicken soup, 1 cup sour cream, 1/2 cup milk, 1 tsp garlic powder, 1/2 tsp black pepper, and 1/4 tsp salt. Stir in the warm onion and garlic mixture. The sauce will be pale and creamy, with a mild garlic smell. It will look loose right now, but that thin consistency is exactly what you want because the spaghetti absorbs liquid as it bakes.

Step 2: Toss the Pasta and Chicken

Add the cooked and drained spaghetti to the bowl of sauce. Use tongs to lift and toss until every strand is evenly coated. Now fold in the 2 cups of shredded chicken, along with 1 cup of the cheddar and 1/2 cup of the mozzarella, stirring until the chicken and cheese are distributed throughout.

The mixture should look marbled with cheese and little shreds of chicken. It is normal for some of the sauce to cling to the sides of the bowl. Scrape it all in, it will melt together in the oven and leave you with a creamy, unified casserole.

Step 3: Bake the Casserole

Butter a 9×13 baking dish lightly, then scrape the spaghetti mixture into it, spreading it into an even layer. Scatter the remaining cheese on top, the last 1 cup of cheddar followed by the last 1/2 cup of mozzarella. Slide the dish into the preheated oven and bake, uncovered, for 25 to 30 minutes.

You will know it is ready when the sauce starts to gently bubble around the edges and the top cheese is completely melted. The center may still look a touch soft, but it will set up as the casserole cools slightly. Do not worry if the sauce seems active at the edges; that bubbling means the pasta is finishing its job of soaking up all that liquid.

Step 4: Broil and Serve

Switch the oven to broil and place the dish under the broiler for 2 to 3 minutes. Watch the whole time; broilers can go from golden to burnt fast. You want the cheese to turn lightly browned and speckled with darker spots, which adds a toasty, savory edge.

Pull the dish out and let it sit on the stovetop or a trivet for 5 minutes before you scoop. That brief rest firms up the casserole so each serving holds its shape. Serve it hot, and watch the plates come back clean.

A Few Notes Before You Start

• Undercook the spaghetti. Boil it about 1 minute less than the package says for al dente. It will keep cooking in the sauce and soften perfectly in the oven without turning mushy.
• Grate your own cheese. Pre-shredded bags contain anti-caking agents that can make the melt a bit grainy. Grating a block takes two extra minutes and gives you a much smoother sauce.
• Try homemade soup. If you have a go-to cream of chicken recipe, use it in place of the can. The texture will be a little looser, so cut back the milk to 1/4 cup.
• Leftover turkey works great. This dish is a smart way to use holiday turkey. Just shred it the same way you would chicken.

Bake times shift a little depending on your dish material, so here is a quick guide.

Storing and Reheating Leftovers

• Refrigerate – Store cooled leftovers in an airtight container for up to 4 days.
• Reheating – Warm individual portions in the microwave, or cover the baking dish with foil and reheat at 350°F until the center is hot, about 15 to 20 minutes.

What to Serve with Baked Chicken Spaghetti

A crisp green salad tossed in a bright vinaigrette cuts through the richness of the casserole and keeps the plate from feeling too heavy. Roasted broccoli with a squeeze of lemon does the same job with a little more substance. If you want something to catch every last bit of sauce, a side of toasted garlic bread never hurts.

Frequently Asked Questions

Can I make baked chicken spaghetti ahead of time?

Yes. Assemble the casserole without the final cheese topping, cover, and refrigerate for up to 24 hours. When you are ready to bake, add the cheese on top, increase the bake time by about 10 minutes, and broil as directed.

Can I use cream of mushroom soup instead?

Absolutely. It swaps in seamlessly and gives the sauce a slightly more earthy, savory note that still works well with chicken and cheese.

What is the best pasta shape to use besides spaghetti?

Short noodles like penne, rotini, or cavatappi hold the creamy sauce really well and make scooping easier. Cook them the same way, about a minute shy of al dente.

Can I freeze this casserole?

You can freeze it either before or after baking. Wrap tightly and freeze for up to 3 months. Thaw overnight in the fridge, then bake or reheat as directed, adding a little extra time if the dish is still cold from the fridge.

Baked Chicken Spaghetti Recipe

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 30 minutes mins

Total Time 45 minutes mins

Servings: 6 servings

Ingredients Method Notes

Ingredients

  

• 12 oz spaghetti, cooked and drained
• 2 cups shredded cooked chicken
• 1 can (10.5 oz) cream of chicken soup
• 1 cup sour cream
• 1/2 cup whole milk
• 1/2 cup diced yellow onion
• 2 cloves garlic, minced
• 1 tbsp unsalted butter
• 1 tsp garlic powder
• 1/2 tsp black pepper
• 1/4 tsp salt
• 2 cups shredded sharp cheddar cheese, divided
• 1 cup shredded low-moisture mozzarella cheese, divided

Method

 

1. Preheat oven to 350°F. Melt butter in a skillet over medium heat. Sauté onion for 4–5 minutes until soft, then add garlic and cook 30 seconds. In a large bowl, whisk soup, sour cream, milk, garlic powder, pepper, and salt. Stir in onion mixture.
2. Add cooked spaghetti and toss to coat. Fold in chicken, 1 cup cheddar, and 1/2 cup mozzarella.
3. Butter a 9×13 dish and spread mixture evenly. Top with remaining cheeses. Bake uncovered 25–30 minutes until bubbly at the edges and melted on top.
4. Broil 2–3 minutes until golden and speckled brown. Let rest 5 minutes, then serve.

Notes

Full-fat sour cream and whole milk make the creamiest sauce, so use them if you can. The mixture will look thin before baking; the spaghetti absorbs the liquid in the oven and leaves you with a velvety casserole. If the top browns too quickly under the broiler, move the dish to a lower rack.