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
I tried one of the reader’s suggestions and used bacon because I had it on hand. Next time I won’t use the bacon fat to caramelize the onions. The bacon taste is good but a bit too fatty for my taste. I used a drizzle of balsamic and a sprinkling of red pepper flakes to cut through that fattiness. I will probably add even more kale or spinach next time time.
This is good to know! I’m glad you liked the recipe overall.
We loved it. Used double the amount of spinach because we didn’t have kale. Next time I’ll add a pinch of cayenne. We like spicy.
Delicious! I love the flavors.
What I did different. I cooked the onions much longer than written before adding the mushrooms. I could not see cooking mushrooms as long as it would take for the onions to caramelize.
I only had a few leaves of kale from my garden, so I used them and added fresh spinach.. I have fresh rosemary, but I also have fresh sage and I cut up a few leaves, minced and added that in also. Topped it all with freshly grated Parmesan cheese
So happy you enjoyed tthe dish, and I love the modifications as well!
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!
YUM — the addition of bacon sounds so good. I’m happy you enjoyed the squash!
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.
That makes me so happy — I’m glad it was a hit!
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.
Yes you can definitely use pre-packaged to save time!
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.
Yay I’m so happy you liked it!