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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
T. says
Loved it!
The fresh rosemary flavor was a crowing feature to the recipe!!!
Donni says
I love caramelized onions, spaghetti squash, greens of all kinds but...while this was tasty, it wasn't pretty as the picture. Not having kale, I used assorted salad greens (arugula, baby spinach, baby kale, etc). If I make this again, I'll not use as much spaghetti squash.
Candice says
Made this tonight for dinner! It was soo good. My husband and I are trying to eat less meat and this was a great, filling meal full of vegetables! I added extra mushrooms and kale. YUM!
Erin says
Thanks Can!! Glad it was a hit 🙂
Rita says
Fantastic recipe! A great addition to my usual spaghetti squash recipes. I added extra onion, shrooms, kale and garlic. Will be finishing it off with a generous amount of fresh parmesan. Comfort food at its finest!
Jen says
I added garlic, twice as many mushrooms and the person who said she added heavy cream inspired me to add a cashew cream sauce. It was a big hit!
Jamie says
I didn't have cheese so I added a splash of heavy cream along with garlic and a dash of cayenne pepper. So good!
Rosie says
Hey Erin! Any idea on the calories per serving for this recipe?
Erin says
Yes--just added!
Michelle W says
Erin you never let me down! This is a quick weeknight meal that is so versatile and not fussy. I went heavy on the onions because we love them - and added some garlic as well. Definitely a meatless Monday win!
Anne Marie says
I added a bag of kale, very delicious
Ashley says
Very tasty. Added some garlic based on the comments, and I think it would also be very tasty with some pine nuts!
HOWEVER, the times reported for prep and cook time are quite misleading! I was anticipating ~35 minutes and then see the step with baking the squash is 45 minutes + 10 minutes to cool. Probably my fault for not reading more thoroughly in full before starting.
JB says
I am not a picky eater and absolutely love vegan food, but I made this tonight and it was a little bland 🙁 Wish I read the reviews before hand about adding the garlic... I think it would have added a little something!
Brooke H says
I noticed the same thing. I added garlic but still found it bland
Miri says
I made this for the first time tonight and it was really good! I was worried it would be too bland and would need sauce or something, but it's not bland at all. I also added garlic, like one person mentioned, and some extra mushrooms (~3/4 cup more) because I bought too many and I think it was the right amount. Overall, great recipe, I'll definitely be making it again!
Erin says
Woohooo! Love that you added garlic too--that sounds delicious. Thanks for your comment 🙂
Kelly says
Came across your recipe today and really looking forward to trying it. Small world, I'm in Pittsburgh too!!
Erin says
That's awesome--love meeting fellow Pittsburghers! I hope you like the recipe 🙂
Kayla says
I in PIttsburgh too!! 🙂 Makes me excited!
Doreen says
Made this tonight for dinner. Excellent! Made (almost) exactly as written, only added a couple cloves of garlic to the onions. Will make again!
Erin says
Amazing, and love that you added garlic!
Mary says
I added spinach and kale and very thinly sliced carrots and zucchini. It's my 3rd time and I just wanted more veggies! I also sautéed a chicken breast earlier and tossed in at the end. We love this s much!
Karen Bartlett says
Just don't use mushrooms!!!!
Try adding zuchinni... or eggplant...or I used sugar snap peas.
Rick says
Very good recipe. I used about 1 tsp of salt. I would use only half of the spaghetti squash (the ones we get are pretty large).
Whitney says
Hi Erin! I am allergic to mushrooms - what alternatives would you suggest? Thanks!!
Gretchen says
I’m looking to try this recipe tonight and I don’t have mushrooms so I’m going to use some roasted eggplant I made the night before...it’ll carmalize nicely with the onions.
Karen Bartlett says
Just don't use mushrooms!!!!
Try adding zuchinni... or eggplant...or I used sugar snap peas.try adding some sundries tomatoes and little crushed red peppers... gives it a great warm kick on cold nights!!
Enam says
This was amazing!! Was looking for something to go as a side dish with Quinoa and this recipe worked perfectly!! Even without the Parmesan cheese and thyme instead of the rosemary, it still tasted fabulous!
As a recently converted vegan, it brings me joy to stumble upon such greatness most especially when my kids approve. :)))
Will definitely be making this again with the rosemary too.
YUM and Thank you!!
Erin says
I'm so glad you and your family enjoyed this recipe!
Shelly Brown says
Really good recipe. We don’t like kale so I used spinach. My husband usually turns his nose up at vegetarian but this time we both had seconds and look forward to leftovers for lunch tomorrow!
Erin says
Woohoo--I'm glad you BOTH enjoyed it!