Monterey Chicken Spaghetti

The first time I made this Monterey chicken spaghetti, it was a Tuesday evening when I had rotisserie chicken leftovers and half a bag of spaghetti. My husband walked through the door and immediately asked what smelled so incredible. That night we ate standing at the counter because neither of us wanted to wait for plates.

Last winter my neighbor was recovering from surgery and I brought over a pan of this casserole. She texted me two days later admitting she ate the entire thing herself over three days straight. Now whenever I mention making it, her whole family gets excited.

Ingredients

• 12 oz spaghetti: Break the noodles in half before cooking for easier serving and better sauce distribution
• 2 cups cooked chicken breast: Rotisserie chicken works beautifully here, but leftover grilled or baked chicken adds even more flavor
• 1 cup red bell pepper and 1 cup yellow onion: These add sweetness and color that balance the rich cheese sauce perfectly
• 2 cloves garlic: Fresh garlic makes all the difference, so avoid the pre-minced stuff in jars
• 2 tbsp butter and 2 tbsp flour: This creates your roux base, so measure carefully for the smoothest sauce
• 2 cups whole milk: Whole milk gives the sauce its luxurious texture, though 2 percent works in a pinch
• 1 cup Monterey Jack and 1/2 cup sharp cheddar: Shred your own cheese from blocks for superior melting
• 1/2 cup chicken broth: Low-sodium broth keeps the dish from becoming too salty
• 1/4 cup sour cream: This secret ingredient adds a subtle tang that cuts through all that rich cheese
• 1/2 tsp salt, 1/4 tsp black pepper, and 1/4 tsp smoked paprika: The smoked paprika is the flavor MVP here
• Additional 1/2 cup Monterey Jack and 2 green onions: Save these for the golden, bubbly topping that makes everyone swoon

Instructions

Preheat your oven and prepare the pasta:

Get your oven to 375 degrees and grease a 9 by 13 baking dish. Boil your spaghetti in salted water until al dente, then drain it well.

Sauté your vegetables:

Melt butter in a large skillet over medium heat. Cook onions and bell peppers for 3 to 4 minutes until they soften, then add garlic for one more minute until fragrant.

Build your cheese sauce:

Stir flour into the vegetables and cook for a minute. Slowly whisk in milk and broth, keep stirring for 3 to 4 minutes until thickened.

Add the cheesy goodness:

Remove the skillet from heat and stir in Monterey Jack, cheddar, salt, pepper, and smoked paprika until melted and smooth. Fold in sour cream.

Combine everything:

Add the chicken and cooked spaghetti to the sauce. Toss until every strand is coated and everything is evenly distributed.

Bake to golden perfection:

Transfer to your baking dish and sprinkle with the remaining Monterey Jack. Bake for 20 to 25 minutes until bubbling and lightly golden on top.

Finish with fresh green onions:

Let it rest for 5 minutes before serving, then scatter sliced green onions across the top for a pop of color and fresh flavor.

Save

This recipe became my go-to for new parents, grieving neighbors, and anyone who needs a meal that says I care without saying a word. Food is love in edible form.

Make Ahead Magic

You can assemble the entire casserole up to 24 hours before baking, just cover it tightly and refrigerate. Add 5 to 10 minutes to the baking time if it goes into the oven cold from the fridge.

Freezing Instructions

Wrap the unbaked casserole in plastic wrap and foil, then freeze for up to 3 months. Thaw overnight in the refrigerator before baking as directed.

Serving Suggestions

A crisp green salad with vinaigrette cuts through the richness beautifully. Steamed broccoli or roasted green beans also make excellent lighter sides.

• Set out hot sauce for those who like a little kick
• Crusty bread is perfect for sopping up extra sauce
• A glass of Chardonnay or light beer complements the creamy cheese sauce

Save

There is something so comforting about a bubbling cheese casserole coming out of the oven. This recipe brings people together one delicious forkful at a time.

Recipe FAQs

→ Can I use rotisserie chicken for this dish?

Yes, rotisserie chicken works perfectly and saves time. Simply shred about 2 cups from a store-bought rotisserie chicken and add it when the recipe calls for cooked chicken breast.

→ Can I make this ahead of time?

You can assemble the entire casserole up to 24 hours in advance, cover tightly, and refrigerate. When ready to bake, you may need to add 5-10 minutes to the baking time since it will be cold.

→ What can I use instead of Monterey Jack cheese?

Colby Jack, pepper Jack for some heat, or additional sharp cheddar all work well as substitutes. The melting quality may vary slightly, but the flavor will remain delicious.

→ Can I freeze this casserole?

Yes, assemble the casserole, wrap tightly in plastic and foil, and freeze for up to 3 months. Thaw overnight in the refrigerator before baking as directed.

→ How do I prevent the sauce from separating?

Stir constantly when adding the milk and broth to the flour mixture, and keep the heat at medium. Remove from heat before adding the sour cream, and stir gently to combine.

→ What sides pair well with this?

A crisp green salad with vinaigrette helps balance the richness. Steamed broccoli or roasted green beans also complement the creamy flavors nicely.