5-Ingredient Chicken Pesto Spaghetti Squash (Paleo, Whole30)

This spaghetti squash recipe has chicken, pesto (homemade or storebought), mushrooms, tomatoes, and spaghetti squash, plus a few spices, and that’s it! The shortest ingredient list 🙌🏼

I first threw this meal together with ingredients I already had in my kitchen. I dug through the freezer and found half of a container of Trader Joe’s Kale Cashew Vegan Pesto (it’s so good and it’s dairy-free!), and I had spaghetti squash on the counter and rotisserie chicken in my fridge.

That meal was so simple to make, and it ended up tasting delicious. So, I’ve recreated this pesto spaghetti squash quite a few times, adding roasted tomatoes (or sun-dried tomatoes) and mushrooms, too. 

I love healthy, nutrient-dense recipes that make big serving sizes, and this recipe fits the bill. I also love when meals are so veggie-packed that you don’t even need a side salad or veggie side dish. 

Where to Buy Spaghetti Squash

You can find spaghetti squash at most grocery stores, especially during the fall and winter. The cheapest spots near me are Trader Joe’s and Lidl. Trader Joe’s prices its squash individually (rather than per pound), which typically ends up being a better deal unless they happen to be tiny.

Anywhere where I can find spaghetti squash for $.99/lb is a good deal!

The brighter the color, the better!

How to Pick a Spaghetti Squash

Go for the ones that are bright yellow (riper) rather than pale yellow. The pale ones tend to be more watery and less flavorful, which I’ve learned the hard way.

Pros of a small quash: you can use it as a bowl and eat right out of the squash.

Pros of a bigger squash: leftovers!

How to Cut a Spaghetti Squash More Easily

If you’ve ever tried to slice a whole spaghetti squash, you know it’s not easy! My favorite hack: poke a few holes in the squash and microwave it for 5 minutes before cutting it. This softens the squash enough to slice more easily and safely with a large knife. 

If you prefer not microwaving it, you can roast the squash whole. This takes a bit longer but eliminates the need to cut the squash in half, and you can add seasonings at the end instead. The microwave-and-slice method is my favorite because the spaghetti squash gets a bit more caramelized when you roast in halves, but I regularly use both methods. 

Once you carefully cut the squash in half with a sharp knife, placed the halves on a parchment-lined baking sheet, and drizzle with avocado oil. You can also sprinkle them with salt, pepper, and garlic powder.

Bake the squash, let it sit until it’s cool enough to touch, and then scoop out and discard the seeds and thin, stringy innards.  I often cook spaghetti squash a day or two in advance, because although it’s easy, it does take a while in the oven.

Next, prep the mushrooms and tomatoes by sauteeing them in a skillet. This recipe is a great way to use leftover grilled chicken or rotisserie chicken, so that part is quick and easy. Finally, I’m obsessed with Trader Joe’s vegan kale pesto since it’s dairy-free! So it works even for Whole30 and Paleo eaters.

Once all of the components (spaghetti squash, mushrooms & tomatoes, cooked chicken, and pesto) are ready, just mix everything together in your sauteeing skillet to keep it all warm or a big bowl if your skillet’s not big enough. Add any additional seasonings (salt, pepper, garlic powder, or maybe some basil!) to taste, and then spoon the spaghetti squash mixture right back to the shells. 

I pick up a spaghetti squash at the store every week and am always trying new ways to make it. Some other favorite ways to use spaghetti squash: 
• Spaghetti squash with turkey meatballs
• Stuffed Mexican spaghetti squash
• Chicken enchilada spaghetti squash 

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5 from 4 votes

5-Ingredient Chicken Pesto Spaghetti Squash

This spaghetti squash recipe has chicken, pesto (homemade or storebought), mushrooms, tomatoes (roasted, sun-dried, or even both), and that's it! The shortest ingredient list 🙌🏼

Prep Time: 15 minutes

Cook Time: 1 hour

Total Time: 1 hour 15 minutes

Servings: 4

Calories: 328kcal

Author: Liv

Ingredients

• 1 Tbsp. olive oil, divided
• Spaghetti squash (1 large, approx. 3-3.5 lbs, or 2 small, approx. 1.5 lbs each)
• 2 cups shredded cooked chicken (about 2 chicken breasts; rotisserie chicken is great here)
• 1/2 cup pesto (I love Trader Joe's dairy-free Vegan Kale Pesto– make sure yours is dairy-free if needed!)
• 1 pint cherry tomatoes (see substitutions)
• 8 oz. Baby Bella or white mushrooms
• 1 tsp. black pepper
• 1 tsp. garlic powder
• 1/2 tsp. salt
• Optional topping (non-Paleo/Whole30): a sprinkle of goat cheese or Parmesan cheese

Instructions

For the Spaghetti Squash

• Preheat oven to 375 degrees. Poke a few holes in your spaghetti squash and microwave it for 5 minutes, then use a large, sharp knife, to slice the spaghetti squash in half lengthwise.
• Place on a baking sheet (use parchment paper for easier clean-up) and drizzle each half with 1/2 tsp. oil and sprinkle with salt, pepper, and garlic powder.
• Bake at 375 degrees F for 45 minutes for a small squash (up to 60 minutes for a large squash). The squash strands should be just barely crunchy still when the squash is ready.
• When squash is done cooking, remove the baking sheet from oven and let the squash cool sit until it's cool enough to handle, at least 10-15 minutes. Scoop out the seeds and gooey innards, and drain any water that may have collected inside the squash during cooking. Fork through the squash to loosen the strands from the shell.

For the Veggies

• Heat 2 tsp. oil in a medium skillet over medium heat and add the sliced mushrooms and sliced cherry tomatoes, cooking until softened.
• Add the squash strands to the skillet of veggies and stir in the pesto and shredded chicken, heating through. Scoop the spaghetti squash mixture back into the two squash shells. 
• Optional: add a sprinkle of parmesan cheese or goat cheese on top and return the baking sheet to the oven to broil for 2-3 minutes, until cheese is just melted.

Notes

If you prefer to not microwave the squash: poke holes in the squash and then bake it whole for 65-70 minutes for a small squash (up to 80 minutes for a large squash). Cut it in half to check doneness.

Substitutions: use 2 regular tomatoes or 1/4 cup chopped sun-dried tomatoes instead of cherry tomatoes, skip the mushrooms, add broccoli, etc.

To speed up the process: You can bake the spaghetti squash a day or two in advance because even though it's easy, it does take a while in the oven. Alternatively, when I've found myself short on time, I've cranked the oven up to 425 and baked the squash for a shorter amount of time, which works in a pinch.

Easy skillet chicken: If you don't already have leftover grilled chicken, rotisserie chicken, etc., here's an easy way to cook skillet chicken to slice or shred. 

In a skillet with a lid, heat 1 Tbsp. olive oil over medium heat. Season chicken breasts with salt and pepper and place chicken breasts in the skillet. Cook for 5 minutes, flip the chicken, and add 1/2 cup water or chicken broth, and cover the skillet with the lid. Cook the chicken for 5-6 more minutes until the chicken is cooked through, adding an additional splash of water if it evaporates. The chicken should register 160 if you check it with a meat thermometer. Let the chicken rest for 5 minutes (to retain its juices) before slicing or shredding.

Nutrition

Serving: 1serving | Calories: 328kcal | Carbohydrates: 25g | Protein: 28g | Fat: 14g | Fiber: 5g | Sugar: 12g