Creamy Cheesy Chicken Spaghetti

This Cheesy Chicken Spaghetti is the kind of dinner that makes a Tuesday feel like something to look forward to. It’s creamy, golden on top, and full of tender chicken and pasta all coated in a garlicky cheese sauce you can make in one skillet.

You won’t need any tricky techniques or special ingredients. Just a handful of pantry staples, a few minutes at the stove, and your oven does the rest.

Why This Cheesy Chicken Spaghetti Works

The sauce is the star here, a real cheese sauce made with a quick roux so it stays silky and never grainy. Using a mix of cheddar and mozzarella gives you both sharp flavor and that perfect stretch when you pull out a forkful.

Because you bake it after mixing, the top gets little crispy cheese edges while the inside stays soft and creamy. It’s the kind of dish that fills the kitchen with a warm, savory smell and always brings everyone to the table without complaint.

Ingredients

• 8 oz spaghetti: regular thickness, not thin. Any long pasta works in a pinch.
• 1 lb boneless skinless chicken breasts: cut into bite-size cubes for quick cooking. Thighs are even juicier.
• 1 tsp salt: divided between the chicken and the sauce.
• 1/2 tsp black pepper
• 2 tbsp unsalted butter
• 2 tbsp all-purpose flour
• 2 cups whole milk: whole milk gives the creamiest result, but 2% is fine.
• 3 garlic cloves: minced. Don’t skip the garlic, it wakes up all that cheese.
• 1 tsp dried Italian seasoning
• 1/4 tsp red pepper flakes: optional, just a whisper of heat.
• 1 1/2 cups shredded sharp cheddar cheese: freshly grated melts best.
• 3/4 cup shredded low-moisture mozzarella cheese: divided, half in the sauce and half on top.
• 2 tbsp grated parmesan cheese: adds a salty, nutty note.
• Fresh parsley: chopped, for serving.

Variations / Substitutions

• Swap the protein: Cubed rotisserie chicken or leftover turkey skips the browning step and still tastes great. Stir it in when you add the cooked pasta.
• Change the pasta: Penne, rigatoni, or even egg noodles hold the sauce well if spaghetti isn’t on hand.
• Add veggies: A handful of frozen peas or steamed broccoli florets stirred in before baking turn this into a one-dish meal.
• Make it smoky: Trade the red pepper flakes for 1/2 tsp smoked paprika and use smoked cheddar if you have it.
• Try a different cheese mix: Gouda melts beautifully, and a little fontina makes the sauce extra rich. If you like it sharper, bump up the parmesan.
• Use gluten-free pasta: Almost any GF spaghetti works, just cook it to the firm side of al dente so it doesn’t fall apart in the bake.

If you like this kind of cheesy comfort, our Skillet Chicken Alfredo is another one-pan favorite worth a look.

How to Make Creamy Cheesy Chicken Spaghetti

Step 1: Boil the Spaghetti

Bring a large pot of salted water to a boil and cook the 8 oz spaghetti until just al dente, about 1 minute less than the package says. You want it with a little bite because it will absorb more moisture in the oven. Drain and set aside.

Look for the pasta to still have a pale, slightly firm core when you test it. Overcooking here means a softer casserole later, so err on the chewy side.

Step 2: Brown the Chicken

While the pasta cooks, pat the chicken cubes dry with a paper towel and season them with 1/2 tsp salt and the 1/2 tsp black pepper. Melt 1 tbsp of the butter in a large oven-safe skillet or wide saucepan over medium-high heat. Add the chicken in a single layer and let it cook without moving for about 3 minutes, until the bottoms get a golden sear. Then stir and cook another 3 to 4 minutes until just cooked through.

The cubes should release easily from the pan and show a little brown color. If they stick, give them another 30 seconds. Transfer the chicken to a plate and set aside, leaving any browned bits in the skillet.

Step 3: Sauté the Aromatics and Make the Sauce

Reduce the heat to medium and add the remaining 1 tbsp butter to the same skillet. Toss in the minced garlic and cook, stirring, for 30 seconds until it smells fragrant and just starts to turn pale gold. Don’t let it brown or it will taste bitter.

Sprinkle the 2 tbsp flour over the butter and garlic and whisk it constantly for 1 minute to cook out the raw flour taste. The mixture will look like a thick paste. Slowly pour in the 2 cups of milk while whisking, making sure to scrape up any browned bits from the bottom of the pan. Add the 1 tsp Italian seasoning, the remaining 1/2 tsp salt, and the optional red pepper flakes. Bring it to a gentle simmer, whisking often, and let it bubble for about 2 minutes until it thickens enough to coat the back of a spoon.

At this point the sauce should be smooth and creamy with a faint garlic smell rising from the pan. Stir in the cheddar, half of the mozzarella (about 1/3 cup), and the parmesan until the cheese melts into a glossy sauce. Taste it and add a pinch more salt if it needs it.

Step 4: Assemble the Casserole

Remove the skillet from the heat. Add the drained spaghetti and the browned chicken to the cheese sauce and toss everything together with tongs or two big spoons until every strand is coated evenly. If your skillet isn’t oven-safe, pour the mixture into a greased 9×13 baking dish.

The cheese sauce will seem generous and a little loose now. That’s exactly what you want because it will set up in the oven. Sprinkle the remaining mozzarella over the top so it melts into a golden cap.

Step 5: Bake and Serve the Spaghetti

Slide the skillet or baking dish into a 375°F (190°C) oven and bake for 25 to 30 minutes. You’ll know it’s ready when the cheese on top is melted and starting to turn golden in spots, and the sauce is bubbling around the edges.

Let the casserole rest for 5 minutes after you pull it out. This helps it set just enough to scoop without falling apart. Spoon it into wide bowls, scatter fresh parsley over each serving, and let everyone fight over the crunchy top bits.

Tips for the Best Cheesy Chicken Spaghetti

• Don’t rinse the pasta after draining.: The little bit of starch left on the spaghetti helps the sauce cling better.
• Freshly grate your cheese whenever you can.: Pre-shredded bags have anti-caking agents that keep the sauce from getting as smooth.
• Watch the broiler if you want a deeper brown top.: After baking, you can switch the broiler on for 1 minute to get those irresistible dark spots. Just don’t step away.
• The sauce thickens as it cools.: If you need to hold the assembled casserole before baking, it’s fine at room temp for 30 minutes. Any longer and the pasta will drink up too much sauce.
• Use a chicken thigh mix for extra insurance against dry meat.: Dark meat stays tender even if you get distracted for a minute.

Bake times by dish size:

Storing Leftovers

Keep any leftovers in an airtight container in the fridge for up to 4 days. The dish reheats well in the microwave, though the top won’t be as crisp. To bring back a bit of that baked texture, warm individual portions in a 350°F oven for 10 minutes covered with foil, then 5 minutes uncovered.

What to Serve with Cheesy Chicken Spaghetti

A simple green salad with a punchy vinaigrette cuts through the richness in just the right way. If you want something warm on the side, roasted broccoli or asparagus tossed with olive oil and lemon zest works beautifully. Garlic bread is the obvious choice, but adding a thin smear of butter and a hit of oregano before toasting makes it feel less ordinary.

Frequently Asked Questions

Can I use pre-cooked chicken?

Yes, just shred or cube about 3 cups of cooked chicken and skip the browning step. Stir it in when you combine the pasta and sauce.

How do I make this ahead of time?

Assemble the entire casserole but hold off on baking. Cover and refrigerate it for up to 24 hours. Add 5 to 10 minutes to the bake time because you will be starting from cold.

Can I freeze cheesy chicken spaghetti?

You can, but the pasta texture softens a bit after thawing. Bake it from frozen at 350°F for 45 to 55 minutes. For best results, freeze it before the final bake step.

What if my sauce is too thin before baking?

Let it simmer on the stovetop for an extra couple of minutes until it visibly thickens. The sauce should easily coat a spoon and leave a clear line when you draw a finger across the back.

I don’t have an oven-safe skillet, what pan should I use?

A standard 9×13 baking dish works perfectly. Just transfer everything after mixing and proceed with the bake as written.

Cheesy Chicken Spaghetti Recipe

Print Recipe Pin Recipe

Prep Time 20 minutes mins

Cook Time 25 minutes mins

Total Time 45 minutes mins

Servings: 4 servings

Calories: 610

Ingredients Method Notes

Ingredients

  

• 8 oz spaghetti
• 1 lb boneless skinless chicken breasts, cut into bite-size cubes
• 1 tsp salt, divided
• 1/2 tsp black pepper
• 2 tbsp unsalted butter
• 2 tbsp all-purpose flour
• 2 cups whole milk
• 3 garlic cloves, minced
• 1 tsp dried Italian seasoning
• 1/4 tsp red pepper flakes (optional)
• 1 1/2 cups shredded sharp cheddar cheese
• 3/4 cup shredded low-moisture mozzarella cheese, divided
• 2 tbsp grated parmesan cheese
• Fresh chopped parsley, for serving

Method

 

1. Cook spaghetti in salted boiling water until just al dente. Drain and set aside.
2. Season chicken with 1/2 tsp salt and the pepper. Melt 1 tbsp butter in a large oven-safe skillet over medium-high heat and brown the chicken on all sides until cooked through, about 6 to 7 minutes. Remove to a plate.
3. Lower heat to medium and melt remaining butter. Sauté garlic 30 seconds, then whisk in flour and cook 1 minute. Gradually whisk in milk, Italian seasoning, remaining salt, and red pepper flakes. Simmer until thickened, 2 minutes. Off heat, stir in cheddar, half the mozzarella, and all the parmesan until smooth.
4. Toss the cooked spaghetti and chicken with the cheese sauce in the skillet. Sprinkle remaining mozzarella on top.
5. Bake at 375°F (190°C) for 25 to 30 minutes until top is golden and edges are bubbly. Let rest 5 minutes, then scoop into bowls and top with parsley.

Notes

If you used a skillet that is not oven-safe, pour the mixture into a greased 9×13 baking dish before topping with cheese and baking. For a spicier kick, add an extra pinch of red pepper flakes or a few cracks of black pepper right before serving. The resting time is important for clean servings so the sauce sets a bit.