Caramelized Onion Spaghetti Squash
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Onions sautéed with butter and olive oil create this scrumptious Caramelized Onion Spaghetti Squash. Mixed with kale and mushrooms for a healthy, colorful meal.
Boy oh boy, do I have a recipe for you! If you’ve never tried spaghetti squash, this recipe will walk you through exactly how to make it, and show you a really tasty way to flavor it. Spaghetti squash is a low carb alternative to traditional pasta, and it has a semi neutral taste (in my opinion), so it’s easy to flavor with a variety of spices.
WHY THIS SPAGHETTI SQUASH RECIPE IS SO GOOD:
- The recipe itself is vegetarian, but you can easily omit the cheese to make it vegan, or add meat (like bacon or sausage) if that’s your thing.
- Minimal ingredients are required — you only need 6 or so ingredients
- It’s flavored with caramelized onions–aka the BEST way to eat onions–plus a combination of butter and olive oil
Can we PLEASE talk about caramelized onions? Have I professed my love for them before? Maybe, but I’m going to do it again. Gahhhh they’re just perfect, and dare I say THE BEST way to eat onions?! Along with that, roasting and eating spaghetti squash is a great way to enjoy a spaghetti-like dish without using actual pasta. This vegetarian spaghetti squash is sure to please ALL eaters!
HOW TO COOK SPAGHETTI SQUASH
FIRST: Slice the spaghetti squash in half length-ways, then brush both sides of it with olive oil and place it cut-side down on a a parchment-lined baking sheet.
Note: This caramelized onion spaghetti squash should come together in less than an hour, give or take depending on the size of your squash. The larger the squash, the longer it’s going to take to roast. Mine was not very big—maybe 2-3 lb.—and it fed both my brother and I, so you definitely don’t need anything too too big, and as for the cheese, it’s completely optional–seriously, your call!
SECOND: Once the squash is roasted, you’ll take it out of the oven and carefully use a fork to remove the “spaghetti”. While the squash is roasting, you should make the caramelized onion mixture. Then, add the cooked squash to the skillet with the caramelized onions, making sure to stir everything together. In addition to the onions, the squash will be flavored with a little rosemary and cheese if you opt to use it, plus kale, mushrooms and plenty of salt and pepper. It’s so simple yet so tasty as well!
OTHER VEGETARIAN DINNER RECIPES
Caramelized Onion Spaghetti Squash
Ingredients
- 1 2-3 lb. spaghetti squash
- 1/4 cup olive oil
- 2 tbsp butter, I used dairy free
- 2 medium yellow onions, peeled and sliced into longer strips if possible
- 1 1/2 cup mushrooms
- 1 cup kale
- 1/4 tsp rosemary, I used fresh, but dried would work too
- Salt and pepper to taste
- Optional: sprinkle of parmesan cheese
Instructions
- Preheat oven to 350°.
- Slice squash in half, remove seeds and place on baking sheet.
- Brush 2 tbsp olive oil on both sides of the squash (1 tbsp per half) and then place face down in the oven.
- While squash is roasting, melt butter and last 2 tbsp oil over medium-high in a large skillet.
- Add onions to skillet, stirring occasionally. After 5 minutes, add mushrooms.
- After approximately 10 minutes, the onions should start to caramelize. If they look like they're burning at all, add an extra tablespoon of oil.
- Add kale to skillet and continue to stir everything together until onions turn a nice golden brown color.
- After 45 minutes, remove squash from oven and allow 10 or so minutes for it to cool off.
- Once slightly cooler, use a fork to remove "spaghetti" from squash and place in a skillet; add rosemary, salt and pepper and stir everything together.
- Add parmesan cheese if you wish and enjoy!
Notes
Nutrition
Delicious! I added golden raisins in the sauté for last few minutes. Also i find it helpful to microwave the whole squash for 3 mins before you roast to soften it up and make it easier for cutting in half.
Yes that’s such a good tip!
Hi! Question – is the nutrition info per serving or for the whole recipe?
Per serving!
It was okay, but definitely needs to be doctored up a bit! I added a few cloves of garlic, feta, spinach instead of kale, and red pepper flakes. Still needs something else, maybe some fire roasted tomatoes? Maybe some umami seasoning? Not sure, but might make again with some additional adjustments! Thanks for the inspo!
I added spinach because I didn’t have kale. Also used a seasoning from Trader Joe’s (mushroom & company multi purpose umami seasoning blend), and topped with fresh Parmesan cheese
Thanks for the 5-star rating, Karen! I’m glad you liked the recipe 🙂
Can you use spinach instead of kale?
Yes!
Wow, made this last night. This will be made once a week. I love this recipe and so easy. I cooked some asparagus to go with it. Perfect meal. Thank you.
Oh my goodness this is amazing! I cooked bite size seasoned chicken pieces for my boys, served them on top with some Parmesan. They loved it and wanted more! They all said “this is a keeper”. Thank you!
Love when meals are kid-approved — thanks so much for the comment!
Tasted superb. Very simple (other than cutting the squash lol), will make again!
Been browsing for more vegetarian/vegan recipes to try and this one was so scrumptious! Added some garlic to it as other people mentioned since I’m a garlic lover. Thanks for sharing!
Dumb question here. It says to roast the squash for 45 mins but do I have to keep cooking the onion and veggies for that long or do i shut it off. And wait for the squash and toss it all together at the end. Sorry I’m A novice cook and follow instructions too exactly maybe lol. Just want to make sure I understand
Not a dumb question! It definitely won’t take the full 45 minutes to caramelize the onions, so you can either start caramelizing them as soon as you put the squash in the oven, then once they’re done just place a lid on the skillet so they stay warm, OR wait 15 minutes or so after the squash has been roasting to start caramelizing them. Hopefully that makes sense!