Easy Southern Chicken Spaghetti Casserole

Here is my favorite Southern Chicken Spaghetti Casserole recipe, with tender chicken, creamy sauce, melted cheese, and pasta all baked together in one comforting dish.

This casserole is a real crowd-pleaser at our dinner table. I love making it on busy weeknights because it feeds the whole family and tastes even better as leftovers the next day. Plus, who doesn’t love a meal where everything gets mixed together in one pan?

What Kind of Chicken Should I Use?

Boneless, skinless chicken breasts are the go-to choice for this casserole, but you’ve got some flexibility here. If you prefer dark meat, boneless thighs work great too and will actually give you more flavor and stay juicier during baking. You can even use a mix of both breast and thigh meat if you want the best of both worlds. Whether you buy fresh or frozen chicken doesn’t matter much – just make sure frozen chicken is completely thawed before cooking. For the easiest prep, look for chicken that’s roughly the same thickness so it cooks evenly, or you can pound thicker pieces to about 3/4 inch thick.

Options for Substitutions

This comforting casserole is pretty forgiving when it comes to swaps:

• Chicken breasts: You can easily use chicken thighs instead – they’ll add more flavor and stay juicier. Rotisserie chicken works great too; just shred about 3 cups of meat and skip the cooking step.
• Spaghetti: Any long pasta will work here – try linguine, angel hair, or even penne if that’s what you have. Cook according to package directions.
• Sharp cheddar cheese: Mild cheddar, Monterey Jack, or a Mexican cheese blend all work well. You could even mix in some cream cheese for extra richness.
• Fresh bell peppers: Frozen bell peppers work fine – just thaw and drain them first. You can also use any color bell pepper or substitute with diced celery for crunch.
• Cream of chicken soup: Cream of mushroom or cream of celery soup work as substitutes. For a homemade touch, mix 1 cup chicken broth with 1/2 cup heavy cream and 2 tablespoons flour.
• Cayenne pepper: If you want less heat, cut the cayenne in half or leave it out completely. For more kick, add a pinch of hot sauce or red pepper flakes.

Watch Out for These Mistakes While Cooking

The biggest mistake you can make with this casserole is overcooking the chicken breasts, which will leave you with dry, tough meat that no amount of cheese can save – cook them just until they reach 165°F and let them rest before shredding.

Another common error is overcooking the spaghetti during the initial boiling step, since it will continue cooking in the oven, so aim for just shy of al dente to prevent mushy noodles in your final dish.

Don’t skip seasoning your chicken while it cooks, and make sure to reserve some of that flavorful pasta water before draining – a splash mixed into your cream of chicken soup will help everything bind together beautifully.

Finally, resist the urge to skip the resting period after baking, as letting the casserole sit for 10 minutes allows the cheese to set and makes serving much cleaner.

What to Serve With Chicken Spaghetti Casserole?

This hearty casserole is pretty filling on its own, but I love serving it with a simple side salad to cut through all that creamy goodness. A basic mixed greens salad with cucumber, tomatoes, and a light vinaigrette works perfectly and adds some fresh crunch to balance out the rich flavors. Garlic bread or buttery dinner rolls are also great for soaking up any extra sauce, and they make the meal feel even more comforting. If you want to add some Southern flair, try serving it alongside some steamed green beans or roasted broccoli to round out the plate.

Storage Instructions

Refrigerate: This casserole keeps really well in the fridge for up to 4 days when covered tightly with foil or plastic wrap. I actually think it tastes even better the next day after all those flavors have had time to meld together. Just cut yourself a portion and you’re good to go!

Freeze: You can definitely freeze this casserole for up to 3 months, which makes it perfect for meal prep. I like to freeze it in individual portions using freezer-safe containers, so I can just grab one serving when I need a quick dinner. Make sure it’s completely cooled before freezing.

Warm Up: To heat it back up, just pop it in the oven at 350°F for about 20-25 minutes if it’s been in the fridge, or 35-40 minutes if frozen. Cover it with foil so the cheese doesn’t get too brown, and remove the foil for the last few minutes if you want the top a bit crispy.

Preparation Time	15-20 minutes
Cooking Time	35-40 minutes
Total Time	50-60 minutes
Level of Difficulty	Medium

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 2300-2500
• Protein: 160-180 g
• Fat: 80-95 g
• Carbohydrates: 210-230 g

Ingredients

For the casserole:

• 1 cup diced bell pepper (diced into 1/2-inch pieces)
• 1/2 tsp cayenne pepper
• 1 tsp garlic powder
• 8 oz dried spaghetti noodles
• 1 can condensed cream of chicken soup
• 1 tsp smoked paprika (for authentic Southern flavor)
• 1.5 lb boneless skinless chicken breasts (cut into bite-sized pieces before cooking)

For the cheese layer:

• 2 cups sharp cheddar cheese, grated, divided (I use Cabot sharp cheddar)

For garnish:

• 1/4 cup sliced green onions (white and light green parts)

Step 1: Prepare Mise en Place and Preheat

• 1 cup diced bell pepper
• 1.5 lb boneless skinless chicken breasts
• 2 cups sharp cheddar cheese, grated, divided
• 1/4 cup sliced green onions

Preheat your oven to 350°F and grease a 9×13-inch baking dish with butter or cooking spray.

While the oven heats, dice your bell pepper into 1/2-inch pieces, cut the chicken breasts into bite-sized chunks, grate your cheddar cheese (keeping half aside for topping), and slice the green onions, separating the white and light green parts.

Having everything prepped and ready will make the assembly process smooth and efficient.

Step 2: Cook the Chicken and Pasta Simultaneously

• 1.5 lb boneless skinless chicken breasts
• 8 oz dried spaghetti noodles

Bring two separate pots of salted water to a boil—one for the chicken and one for the pasta.

Add the chicken pieces to the first pot and simmer for 6-7 minutes until cooked through and no longer pink inside.

At the same time, add the dried spaghetti to the second pot and cook for 8-10 minutes until just al dente (slightly firm to the bite).

Drain both the chicken and pasta in separate colanders.

Working with two pots at once saves time without sacrificing quality.

Step 3: Build the Casserole Base

• cooked chicken from Step 2
• cooked pasta from Step 2
• 1 can condensed cream of chicken soup
• diced bell pepper from Step 1
• 1 tsp smoked paprika
• 1/2 tsp cayenne pepper
• 1 tsp garlic powder
• 1 cup grated cheddar cheese

In a large mixing bowl, combine the cooked chicken from Step 2, cooked pasta from Step 2, cream of chicken soup, diced bell pepper from Step 1, smoked paprika, cayenne pepper, and garlic powder.

Stir in half of the grated cheese from Step 1, mixing everything thoroughly until the ingredients are evenly distributed and the cheese begins to melt slightly from the residual heat.

This creates a cohesive, flavorful base for your casserole.

Step 4: Assemble and Top the Casserole

• casserole mixture from Step 3
• 1 cup grated cheddar cheese

Transfer the casserole mixture from Step 3 into your prepared baking dish, spreading it evenly.

Top with the remaining grated cheddar cheese from Step 1, distributing it evenly across the surface.

I like to use the extra cheese generously on top—it creates that golden, crispy-edged layer that makes this Southern-style casserole so comforting.

Step 5: Bake Until Golden and Bubbly

Bake the casserole in your preheated 350°F oven for 25-30 minutes, until the top is golden brown and the edges are bubbling.

You’ll know it’s ready when you see a light golden color on the cheese and steam beginning to escape from the sides.

The casserole will continue to set slightly as it cools.

Step 6: Rest and Garnish

• sliced green onions from Step 1

Remove the casserole from the oven and let it rest for 5 minutes before serving.

This brief resting period allows the casserole to set, making it easier to portion without falling apart.

Top with the sliced green onions from Step 1 just before serving, adding a fresh, bright finish to balance the rich, creamy flavors.