Spaghetti Squash Chicken Casserole

Instead of stuffing each spaghetti squash with a filling, this casserole incorporates everything into one easy baking dish. A combination of spaghetti squash, tomatoes, zucchini, and chicken are all mixed together and topped with cheese. Once baked, it’s the perfect, hearty meal for a weeknight or special occasion!

Why this recipe works.

Spaghetti squash has a few hurdles to overcome. First, the skin is tough and can be hard to slice through. Second, the squash must be baked in the oven before the noodle-like interior is ready to use. Last, the interior does not have an abundance of flavor. The answer is this casserole. Roasting the halved squash alongside chicken breasts in the oven creates a tender interior that can be easily scraped out. Layers of flavor are added with pan-fried zucchini, sautéed onion with pepper, and Italian seasoning. All ingredients are mixed together with tomatoes and peas the casserole is topped with cheese and baked in the oven until the cheese is bubbling. The result is a flavorful casserole. All the cozy casserole flavors with a fresh take.

Everything you’ll need to make this recipe.

• Spaghetti squash is football-shaped with white-yellow skin. Once they bake, the interior flesh becomes tender. The flesh is spaghetti-sized tender squash.
• Zucchini can take on a new flavor when sautéed in oil until brown. Make sure to add no salt until it is brown. Salt brings out moisture and inhibits browning.
• Cherry tomatoes will have a much better taste than larger tomatoes during the winter months. The smaller tomatoes are always sweet and ripe.
• Italian seasoning is a blend of dried herbs that compliment the vegetables and add a perfect flavor to the casserole.

Here’s how to make this recipe.

1. Roast the squash and chicken. Slice the ends off of each spaghetti squash, then slice in half. Scoop out the interior seeds and pith and discard. Place each half of squash face up on a parchment-lined baking sheet. Also place the chicken breasts on the parchment. Drizzle the squash and chicken with olive oil, salt, and black pepper. Then flip the squash over so the interior cavity is facing down. Place the pan in the preheated 375°F oven and bake for 45 to 60 minutes. The chicken will cook faster than the squash, so remove the breasts when they reach 160°F. When the squash has finished roasting, remove it from the oven and set aside to cool.

2. Brown the zucchini. Slice the zucchini in half lengthwise, then cut into ¼-inch thick pieces. In a skillet with hot oil, add each piece of zucchini. Let the zucchini cook, then flip once browned. Let the other side brown, then remove the zucchini from the skillet.

3. Prepare the tomato mixture. Chop an onion and bell pepper into a fine dice. Add these two ingredients to the hot oil in the skillet along with salt and mix to incorporate. Cut the cherry tomatoes in half and mince up the garlic. When the onion and bell pepper mixture has softened, add in the tomatoes and garlic. Also add the black pepper, red pepper flakes, Italian seasoning, and chicken stock. Stir everything together and let the mixture sauté. When the tomatoes have softened, remove it from the heat. The tomato mixture will likely have some liquid remaining in the pan, which is to be expected.

4. Scoop out the squash. In a large bowl, use a spoon to scoop out the interior flesh of each half of spaghetti squash. Then break up the flesh using your hand or a spoon.

5. Mix everything together. Slice or shred the cooked chicken breasts once they cool slightly. Add the chicken to the bowl with the spaghetti squash along with the peas, cooked zucchini, and tomato mixture. Mix everything together and pour into a greased 9×13 baking dish. Smooth out the top and sprinkle with the mozzarella cheese and Parmesan cheese.

6. Bake the casserole. Place the baking dish in the preheated 375°F oven and bake for 35 to 45 minutes until the cheese has melted and the mixture has warmed through. Remove it from the oven and serve immediately.

These pro tips will make this recipe a success.

• If your spaghetti squash has any brown spots, simply slice them out. As long as the entire squash is not brown or discolored, it can be used, especially as the squash will be scooped out into strings.
• When scooping out the interior of each spaghetti squash, a grapefruit spoon works perfectly!
• To achieve a perfectly crisp exterior to the zucchini, do not add salt while sautéing. Salt will draw out moisture while it’s cooking, which is not desirable as it will not create a crispy crust. Without salt, the zucchini will end up crisp and flavorful.
• If you want the top of the casserole to be slightly browned and golden, turn on the broiler in the last minute of baking. This blast of heat will darken the cheese on top and add a bit of extra crispness.

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