A nostalgic classic for many, cheesy chicken spaghetti is the staple weeknight dinner you can rely on. If you didn’t grow up with this comfort food, allow me to introduce you to your new favorite easy weeknight dinner. Chicken, spaghetti, and veggies combine with a creamy, cheesy sauce for a baked and bubbling casserole that’s just as perfect for busy weeknights as it is for parties. The best part? The leftovers almost taste even better.

Keep reading on for all of my top tips on making and serving this family favorite:

What People Are Saying:

"So flavorful without being too rich. It is definitely an amazing comfort meal!" - cherrycoke

"This is comfort food, through and through. The chicken is nicely seasoned and it's a creamy, cheesy weeknight dinner." - jan3354

How To Make Chicken Spaghetti

INGREDIENTS

Spaghetti: As the name of the dish implies, the ideal noodle for chicken spaghetti is indeed spaghetti. The long, thin noodles are perfect for picking up the creamy sauce, while still giving a bit of a bite and heft—as opposed to a pasta like angel hair, which pairs better with a lighter sauce.
Yellow Onion: Onion adds aroma and flavor to the casserole, that, after sauteing and baking, becomes translucent and melt-in-your-mouth soft.
Red Bell Pepper: Bell peppers have a pleasantly, almost bitter, vegetal taste with a fair bit of sweetness as well, almost like the sweetness of a red tomato, and add a nice bite when raw or cooked. They work especially well here in a dish that is primarily creamy and savory.
Chicken Breasts: One of the beauties of this recipe is how versatile it is. Though I am opting for chicken breasts here, you would be just as well to substitute them out for chicken thighs, or another protein like mushrooms or other veggies. Similarly, I find if you do stick to chicken, boneless, skinless chicken works best.
Chili Powder: I’m not using a ton of chili powder here, but the little bit that is tossed in adds a nice smokiness and a hint of spice to the dish that helps elevate it from good to great. This is another ingredient that could be substituted out for another spice like red pepper flakes or cayenne.
Butter & All-Purpose Flour: This is the base for an innumerable many sauces and for good reason. This simple combination of butter and flour provides the base for our sauce that is easy to adjust by simply adding more flour or liquid respectively. Just be sure not to burn the mixture before adding in the liquid.
Whole Milk: Whole milk is the best bang for your buck here. We want something with enough fat to bond the sauce, as opposed to another option like skim milk. You could substitute in heavy cream instead, but in my opinion that makes the sauce just a little too heavy.
Chicken Broth: If you wanted to make this dinner into a vegetarian option, you could substitute this out for vegetable broth—and take the chicken out as well—but I think the nice savory flavor of classic chicken broth brings out even more chicken flavor in the dish while also providing necessary moisture.
Cheddar: Shredded cheddar cheese is sharp enough to cut through the other flavors here, and also melts very well when baked to create the classic gooey almost-crust on top.

STEP-BY-STEP INSTRUCTIONS

Start off by preheating your oven to 350° and bringing a large pot of salted water to boil. Once the water has come to a rolling boil, add in the spaghetti and cook, stirring occasionally to ensure the pasta doesn’t stick together and cooks evenly, until al dente. This should take about 7 minutes.

Then, in another large pot, heat olive oil over medium heat and add in onion and bell pepper to cook. Stir the mixture occasionally as it cooks until the onions have turned somewhat translucent and the whole mixture has softened considerably. This should take around another 7 minutes. Once cooked, transfer the onion and pepper mixture to a plate.

Chicken Spaghetti

Season the chicken breasts all over with salt, pepper, and chili powder. Then, in the pot that you cooked the onion and bell pepper, cook the chicken, stirring occasionally, for about 5 minutes until the chicken has a nice golden brown color to it, then remove the chicken from the heat and similarly set aside.

Chicken Spaghetti

Once more in the same pot, add in the butter and once melted, whisk in the flour, continually whisking as it cooks for about 1 minute. Then add in the whole milk and chicken broth and stir to combine. Cook this mixture, stirring occasionally, for another 5 minutes until the sauce has thickened but is still pourable. If your mixture is too dry add in a little bit more liquid. Too wet, sprinkle in some more flour.

Chicken Spaghetti

To this sauce, add in the spaghetti, vegetables, chicken, and the cheddar cheese and stir to combine. Then transfer this mixture to a baking dish and top with more cheese.

Carefully transfer the dish into the prepared oven and bake the mixture for about 45 minutes until the chicken spaghetti is hot and bubbly. Once cooked, remove the casserole from the oven and top with fresh parsley for a green, herbaceous bite.

Chicken Spaghetti

The full list of ingredients and instructions can be found in the recipe below.

Recipe Tips

What is chicken spaghetti? If you didn't grow up with chicken spaghetti, you can think of it as being pretty similar to mac 'n' cheese, but amped up with chicken and spaghetti (duh). This casserole combines chicken breasts, red bell peppers, onion, chicken broth, and a creamy, cheesy sauce for a baked casserole that is perfectly adaptable. Swap out the chicken breasts for chicken thighs or rotisserie, add in even more veggies, or use a slightly thicker noodle shape. Like most of our casseroles, you can really play around here.

What To Serve With Chicken Spaghetti

Because this dish is rich and creamy, I love to serve it with some of my favorite veggie sides and salads (although I’d never say no to some copycat Red Lobster biscuits or cheesy funeral potatoes). Roasted green beans, caramelized Brussels sprouts, or roasted delicata squash would all be great options.

Storage

If you have any leftovers (lucky you!), store them in an airtight container in the refrigerator for 3 to 4 days.

Yields: 4 servings

Prep Time: 15 mins

Total Time: 1 hour

Ingredients

1 lb.
spaghetti
1 tbsp.
extra-virgin olive oil
1
yellow onion, chopped
1
red bell pepper, seeds and ribs removed, chopped
1 lb.
boneless, skinless chicken breasts, cut into 1" pieces
Kosher salt
Freshly ground black pepper
1/2 tsp.
chili powder
3 tbsp.
unsalted butter
3 tbsp.
all-purpose flour
2 c.
whole milk
1 c.
low-sodium chicken broth
2 1/2 c.
shredded cheddar, divided
Chopped fresh parsley, for serving

Directions

Preheat oven to 350°. In a large pot of boiling salted water, cook spaghetti, stirring occasionally, until al dente according to package instructions, about 7 minutes.
Meanwhile, in another large pot over medium heat, heat oil. Add onion and bell pepper and cook, stirring occasionally, until softened, about 7 minutes. Transfer to a plate.
Season chicken all over with salt, pepper, and chili powder. In same pot over medium-high heat, cook chicken, stirring occasionally, until golden brown, about 5 minutes. Transfer to another plate.
In same pot over medium heat, melt butter. Whisk in flour and cook, whisking constantly, until fragrant and combined, about 1 minute. Add milk and broth and cook, stirring occasionally, until thickened, about 5 minutes.
Stir in spaghetti, vegetables, chicken, and 1 1/2 cups cheddar. Transfer to a 13" x 9" baking dish. Top with remaining 1 cup cheese.
Bake chicken spaghetti until bubbly, about 45 minutes. Top with parsley.