Butternut Squash Chicken Casserole {Gluten-Free}
This easy Gluten-Free Butternut Squash Chicken Casserole is low-carb comfort food at its finest. Made with boneless chicken breasts, spiralized butternut squash, rice, and a creamy garlic mushroom sauce, you’ll be coming back for seconds. You’ll never miss having pasta in this hearty, satisfying dish.
One-pan meals are the best, especially when they involve cheese. I like to make life easier by conveniently cooking everything in one dish. I have a few more favorite one-dish meals on the blog, like this Greek Chicken Stew (a must try!), Spaghetti Squash Meatball Casserole (also a family favorite), and a healthier Chicken Vegetable Casserole that’s packed with a LOT of veggies. There are plenty more, to name a few.
I used to make a version of this chicken casserole recipe that involved egg noodles, but I wanted to switch up the pasta with a small amount of rice combined with a nutrient-dense vegetable to reduce the carbohydrates since there is more fat in this dish (why it tastes SO good ;). I knew that butternut squash would hold up well in a baked dish and the results were amazing. We declared this creamy gluten-free chicken butternut squash casserole a winner, winner, chicken dinner!
Ingredients you’ll need
- Extra virgin olive oil
- Butter
- Mushrooms
- Shallots, finely chopped
- Fresh garlic, minced
- Gluten-free all-purpose flour *I used King Arthur Brand
- Whole milk
- Chicken broth- or stock
- Chicken boullion- *I use and recommend the Better than Boullion brand
- Fresh thyme *leaves pulled from the stem
- Seasonings- salt, fresh cracked pepper
- Spiralized butternut squash- I buy it already cut for convenience
- Microwave Ready Rice I used Uncle Ben’s long-grain white rice *uncooked
- Cooked boneless chicken breast chopped into bite-size pieces
- Parmesan cheese- shredded
How to make gluten-free chicken casserole with butternut squash
Step 1. Preheat oven to 350 degrees Fº and heat a large skillet on medium heat and melt the butter and olive oil.
Step 2. Add the mushrooms and cook for 3-4 minutes. Add shallots and garlic. Sauté until the mushrooms are lightly browned and the garlic is fragrant.
Step 3. Whisk in flour and stir for 1 minute. Then add the milk, broth, and seasonings. Stir until sauce has thickened, about 3-4 minutes.
Step 4. Add in squash “noodles”, chicken, uncooked Ready Rice, and 1/4 of the Parmesan cheese. Stir until combined.
Step 5. Pour into a 9×13 inch casserole dish sprayed with olive oil spray and top with remaining cheese. Bake for 30-35 minutes until bubbly and all the cheese has melted.
Recipe tips
- Let it rest. Resist the temptation to dig in immediately and give it a few minutes to cool slightly. This allows the flavors to meld together and the casserole to set, resulting in a more cohesive dish with better texture.
- To make ahead, follow the recipe instructions and assemble the casserole the day before, but don’t bake it. Instead, cover the dish and keep it in the fridge until you are ready to bake it. You can also bake it the day before and then reheat it in the oven before serving.
This recipe makes eight generous servings with less than 360 calories each. I like to serve this dish with steamed broccoli or a side salad. It would also be amazing over cauliflower mashed potatoes.
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Butternut Squash Chicken Casserole
Ingredients
- 1/4 cup extra virgin olive oil
- 1/4 cup butter
- 8 oz fresh mushrooms
- 2 shallots ,finely chopped
- 1 clove garlic ,minced
- 1/3 cup all-purpose gluten-free flour *I used King Arthur Brand
- 1 cup whole milk
- 2 cups chicken broth
- 1 tsp chicken boullion *I used Better than Boullion brand
- 1 tbsp fresh thyme *pull leaves from stem
- 1/2 tsp salt
- 1 tsp fresh cracked pepper *or more to taste
- 16 oz spiralized butternut squash
- 8.5 oz bag microwave Ready Rice I used Uncle Ben's long-grain white rice *uncooked
- 24 oz cooked boneless chicken breast chopped into bite-size pieces
- 1/2 cup shredded Parmesan cheese divided (you can use an extra 1/4 cup for topping if you like it cheesier)
Instructions
- Preheat oven to 350 degrees F.
- Melt butter and olive oil in a large skillet on medium heat.
- Add mushrooms and cook for 3-4 minutes.
- Add shallots and garlic.
- Sauté until mushrooms are lightly browned and garlic is fragrant.
- Whisk in flour and stir for 1 minute.
- Add milk, broth, and seasonings. Stir until sauce has thickened, 3-4 minutes.
- Add in squash "noodles", chicken, uncooked Ready Rice, and 1/4 of the Parmesan cheese. Stir until combined.
- Pour into a 9×13 inch casserole dish sprayed with olive oil spray and top with remaining cheese.
- Bake for 30-35 minutes until bubbly and all of the cheese has melted.
Notes
- Let it rest. Resist the temptation to dig in immediately and give it a few minutes to cool slightly. This allows the flavors to meld together and the casserole to set, resulting in a more cohesive dish with better texture.
- To make ahead, follow the recipe instructions and assemble the casserole the day before, but don’t bake it. Instead, cover the dish and keep it in the fridge until you are ready to bake it. You can also bake it the day before and then reheat it in the oven before serving.
Nutrition
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It is SO cold here today (and this weekend) and a meal like this sounds PERFECT!
I don’t know about you, but I’m counting the days until spring! It’s definitely a great dish on a chilly evening. 🙂
So many yummy ways to use butternut squash!
Have you ever made this with small cubes of squash rather than spirals? Do you think this would be ok? We don’t have a spiralize and it seems the quickest easiest way without one.
Hi Bre! I haven’t tested it with cubed butternut, but it should work. You may need to adjust the cook time a bit. If you try it, please let me know how it turns out. 🙂