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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
Instructions
- Preheat oven to 350°.
- Slice squash in half, remove seeds and place on baking sheet.
- Brush 2 tablespoon olive oil on both sides of the squash (1 tablespoon per half) and then place face down in the oven.
- While squash is roasting, melt butter and last 2 tablespoon 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
Carrie Randall says
I just made this but I crisped some bacon in the skillet first, drained off most of the bacon fat, and added some asparagus that I needed to you. Amazing! Thank you for your recipe!
Erin says
YUM -- the addition of bacon sounds so good. I'm happy you enjoyed the squash!
Karen says
Delicious. I actually made it for thanksgiving for my non-meat eaters, and it was an all time hit! I also share it when anyone says they are going to make spaghetti squash.
Erin says
That makes me so happy -- I'm glad it was a hit!
Michelle says
Do I need to buy a whole squash and roast it? Can you use pre-packaged fresh spaghetti squash instead ? I know you won’t get the roasted flavour but if your pressed for time or not sure if you like squash and don’t want to spend so much time.
Erin says
Yes you can definitely use pre-packaged to save time!
Amy says
Made this at work (nanny) and my bosses and I LOVED it!!! t
This was 2 nights ago and I'm making it at home for some family/friends! AMAZING!! Only difference from original is I use spinach as i HATE kale! 🤢
THANK YOU.
Erin says
Yay I'm so happy you liked it!
Joni Arison says
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.
Erin says
Yes that's such a good tip!
Maria says
Hi! Question - is the nutrition info per serving or for the whole recipe?
Erin says
Per serving!
Sarah says
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!
Karen says
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
Erin says
Thanks for the 5-star rating, Karen! I'm glad you liked the recipe 🙂
Stephanie says
Can you use spinach instead of kale?
Erin says
Yes!
laura maxwell says
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.
Jenny says
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!
Erin says
Love when meals are kid-approved -- thanks so much for the comment!
Amelie says
Tasted superb. Very simple (other than cutting the squash lol), will make again!
Heather Copfer says
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!
Courtney says
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
Erin says
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!