If you love comforting, cheesy pasta dishes that come together without fuss, this Creamy Chicken Spaghetti will become a weeknight favorite. It’s rich, saucy, and full of familiar flavors—tender shredded chicken, melted mozzarella, and a silky, creamy sauce that clings to every strand of spaghetti. The recipe uses simple pantry staples and a handful of fresh ingredients, so you can have dinner on the table quickly without sacrificing that cozy, home-cooked feeling.

This version keeps things straightforward while still feeling a little special. A touch of butter and garlic jump-start the sauce, green bell pepper adds brightness, and a splash of heavy whipping cream gives the dish that signature luscious texture. Diced tomatoes tucked into the bake give pleasing bursts of acidity, balancing the richness of the cheese. The result is pasta that’s creamy, satisfyingly cheesy, and built on dependable flavors everyone at the table will appreciate.

Why you’ll love this recipe

Simple ingredients you probably already have on hand.
Comforting, creamy texture with plenty of cheesy pull.
Quick assembly—perfect for busy weeknights or a relaxed weekend meal.
Flexible: swap in leftover cooked chicken or rotisserie chicken for speed.

Ingredients

▢10 ounces dry spaghetti noodles (*)
▢2 tablespoons unsalted butter (¼ stick)
▢1 clove garlic (minced)
▢½ green bell pepper (chopped **)
▢¼ cup all-purpose flour
▢1 teaspoon Italian seasoning
▢¼ cup heavy whipping cream
▢½ cup chicken broth
▢½ cup milk
▢1½ cups shredded mozzarella cheese
▢salt and pepper (to taste)
▢2 cups shredded cooked chicken
▢14 ounces diced tomatoes (drained) (1 can)

Notes on ingredients: Use a cooked, fully cooked, lean chicken that fits your dietary preferences. The shredded chicken can be from a roasted whole bird, poached breasts, or store-bought rotisserie-style poultry prepared and shredded. The recipe calls for both heavy whipping cream and milk to create a sauce that’s rich but not overly heavy. Drain the diced tomatoes to prevent the casserole from becoming watery; a tin that’s been poured into a sieve for 30–60 seconds works well.

Equipment

Large pot for boiling spaghetti
Large skillet or saucepan
Measuring cups and spoons
Wooden spoon or spatula
Baking dish (about 9×13 or similar shallow casserole)
Colander or strainer

Step-by-step directions

Follow these clear, ordered steps to make the dish. I kept the same sequence as the original formula but rewrote each instruction for clarity and flow.

Preheat and prepare. Preheat your oven to 350°F (175°C). Bring a large pot of salted water to a boil while you prepare the other components.
Cook the spaghetti. Add the 10 ounces of dry spaghetti noodles to the boiling water and cook until al dente according to the package directions (usually 8–10 minutes). Drain the spaghetti in a colander and set aside.
Melt butter and sauté aromatics. While the pasta cooks, melt 2 tablespoons unsalted butter (¼ stick) in a large skillet over medium heat. Add 1 clove minced garlic and the chopped ½ green bell pepper. Sauté for 2–3 minutes, stirring often, until the pepper softens slightly and the garlic becomes fragrant but not browned.
Create a roux. Sprinkle ¼ cup all-purpose flour over the softened vegetables and stir constantly for about 1 minute to cook the raw flour taste out. This forms the base of your sauce and will thicken the liquids.
Season and add liquids. Add 1 teaspoon Italian seasoning to the pan. Gradually whisk in ¼ cup heavy whipping cream, ½ cup chicken broth, and ½ cup milk. Whisk or stir continuously to combine, smoothing out any lumps. Allow the mixture to simmer gently for 2–3 minutes until it begins to thicken slightly.
Finish the sauce. Reduce the heat to low. Stir in 1½ cups shredded mozzarella cheese, mixing until the cheese melts and the sauce becomes creamy and cohesive. Taste the sauce and season with salt and pepper to your preference. Remember the shredded chicken and cheese add saltiness, so start lightly and adjust.
Combine pasta, chicken, and tomatoes. Transfer the drained spaghetti to a large mixing bowl or return it to the pot off the heat. Add the 2 cups shredded cooked chicken and the drained 14 ounces diced tomatoes (one can). Pour the creamy cheese sauce over the spaghetti, chicken, and tomatoes. Toss gently but thoroughly so the sauce coats all of the spaghetti and the ingredients are evenly distributed.
Assemble in baking dish. Spoon the sauced spaghetti mixture into a lightly greased baking dish (about 9×13 or a similar shallow casserole). Spread it into an even layer so the top has good contact with heat and will brown slightly.
Bake until bubbly. Place the baking dish in the preheated 350°F oven and bake for 20–25 minutes, or until the casserole is bubbly around the edges and the top is slightly golden. If you prefer a browned, slightly crispy top, you can turn the oven to broil for the final 1–2 minutes—watch carefully to avoid burning.
Rest and serve. Remove the casserole from the oven and let it rest for 5–10 minutes before serving. This rest time allows the sauce to set slightly, making it easier to portion and giving the flavors a bit of time to meld.

Serving suggestions

This Creamy Chicken Spaghetti is a full meal on its own, but here are a few ways to round it out:

Light green salad with a simple lemon vinaigrette to cut through the richness.
Steamed green beans or roasted broccoli for a bright, textured side.
Warm crusty bread or garlic bread to mop up any extra sauce.

Make-ahead and storage tips

To make ahead: prepare the casserole through step 8, cover tightly, and refrigerate for up to 24 hours. Bake covered at 350°F for 30–35 minutes, then uncover and bake until bubbly and slightly golden, about 10 more minutes.
Leftovers: store cooled leftovers in an airtight container in the fridge for up to 3 days. Reheat gently in the microwave or in a covered skillet over low heat, adding a splash of milk if the sauce seems thickened.
Freezing: you can freeze the baked casserole for up to 2 months. Thaw overnight in the fridge before reheating, then warm in a 350°F oven until heated through.

Variations and swaps

Want to put a twist on the classic? Here are a few easy variations that keep the spirit of the dish while adding new textures and flavors:

Vegetable boost: Stir in 1 cup frozen peas, chopped spinach, or corn when you combine the sauce and pasta for added color and nutrition.
Spicy kick: Add a pinch of crushed red pepper flakes to the sauce while it simmers for a gentle heat.
Cheese swap: Stir in a handful of grated Parmesan with the mozzarella for a nutty depth, or use provolone for a milder melt.
Short pasta: If you prefer, use penne or rotini instead of spaghetti; adjust cooking time to package directions.

Why this method works

The technique here balances creamy sauce development with a quick bake that lets flavors mingle without drying the pasta. Cooking the noodles al dente ensures they continue to finish in the oven without becoming mushy. The roux (flour cooked in butter) gives the sauce body, while the combination of heavy cream and milk creates a silky mouthfeel without being overly heavy. Finishing in the oven brings everything together and gives the top a pleasant texture that contrasts with the creamy interior.

Quick tips for success

Don’t overcook the spaghetti in the pot—al dente is ideal because the pasta will finish cooking a bit in the oven.
Drain the diced tomatoes well to avoid a watery casserole.
Shred the chicken finely so it disperses evenly through every bite.
If the sauce looks too thick before baking, stir in a tablespoon or two of chicken broth or milk to loosen it.

Final thoughts

This Creamy Chicken Spaghetti is the kind of dish that feels indulgent but is rooted in everyday pantry staples. It’s comforting, cheesy, and reliably delicious—perfect for family dinners, potlucks, or nights when you want something easy but satisfying. The flavors are familiar, the texture is cozy, and the steps are simple. Try it once and it’ll likely earn a spot in your regular dinner rotation.

Enjoy this warm, cheesy bake straight from the oven with a crisp salad and plenty of napkins—this one is meant to be savored.

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Creamy Chicken Spaghetti

A comforting baked spaghetti casserole with tender chicken, creamy sauce, tomatoes, and melted mozzarella.

Prep Time10

Cook Time50

Total Time1

Ingredients

10 ounces dry spaghetti noodles
2 tablespoons unsalted butter ¼ stick
1 clove garlic minced
1/2 green bell pepper chopped
1/4 cup all-purpose flour
1 teaspoon Italian seasoning
1/4 cup heavy whipping cream
1/2 cup chicken broth
1/2 cup milk
1 1/2 cups shredded mozzarella cheese divided
salt and pepper to taste
2 cups shredded cooked chicken
14 ounces diced tomatoes drained (1 can)

Instructions

Preheat the oven to 375°F and grease a 9×13-inch baking dish; set aside.
Bring a large pot of salted water to a boil and cook the 10 ounces of spaghetti until al dente according to package directions; drain and set aside.
In a large skillet over medium-high heat, melt 2 tablespoons unsalted butter, then sauté the minced garlic and chopped green bell pepper until the pepper is tender, about 3–4 minutes.
Sprinkle in ¼ cup all-purpose flour and 1 teaspoon Italian seasoning, stirring constantly and cooking for about 1 minute to remove the raw flour taste.
Slowly whisk in ¼ cup heavy whipping cream, ½ cup chicken broth, and ½ cup milk; bring to a simmer and cook, stirring frequently, until the sauce thickens slightly.
Remove the skillet from the heat and stir in ½ cup of the shredded mozzarella until melted; season the sauce with salt and pepper to taste.
Add the drained spaghetti, 2 cups shredded cooked chicken, and the drained 14-ounce can of diced tomatoes to the skillet and toss gently until everything is evenly coated.
Transfer the mixture to the prepared baking dish, sprinkle the remaining 1 cup of shredded mozzarella evenly over the top, and spread into an even layer.
Bake in the preheated oven for 15–20 minutes, until the cheese is melted and bubbly and the edges are lightly browned; let rest a few minutes before serving.