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 absolutely adore mushrooms, onions, and spaghetti squash so I expect to love this recipe, especially based on other comments. I can’t wait to try it. Perhaps today!
Just last week I stumbled across a Pinterest post on how to properly cut and cook spaghetti squash. It was very informative. Turns out I was doing it wrong, I had been cutting it lengthwise, cutting the strands in half. The strands run around the circumference of the squash so i should cut across the squash, not lengthwise. There were more re tips about the best cooking methods, too. See How to Cook Spaghetti Squash @eatwithinyourmeans or search Pinterest for the same title by Eatwithinyourmeans.
This is one of my favorite recipes ever! I love it. It tastes so good!
I don’t count calories and therefore don’t provide nutrition info. However, you can input the ingredients into an app like MyFitnessPal, etc.
Just made this and it is SO good! This was my first time making spaghetti squash – I’m trying to start cooking more as well as cooking healthier.
Loved it!
I’m so glad you liked it Alina!
are the mushrooms sliced or whole?
do you really mean to oil the skin of the squash or just the cut part?
is the kale chopped? small pieces or large or ?
I am making this now, so guessing the above answers, but would love to know what you intended. the flavors sound wonderful and i’ve never made or eaten spaghetti squash before…
Hi Anne–to answer your questions: sliced mushrooms preferably, you’ll want to oil the cut edges and the outside of the squash, and it doesn’t matter the size of the kale because it’ll shrink up as soon as you cook it in the butter/oil. Let me know how you like it!
It was great!
I sliced the mushrooms and rough chopped the kale. Left out the rosemary.
Next time will add garlic I think. Thanks!
How can I get the nutrition facts on this?
This has been my go to comfort dish since discovering spaghetti squash 30+ years ago… I also add some sundried tomatoes and nitrate free bacon ..
On the rare chance there are leftovers.. warm it up and drop a fried or poached egg on top!!
Yum!!! I replaced the butter with ghee as I don’t eat dairy. Thank you!
Hi I just wanted to comment that Ghee is butter. It is just clarified butter with the fat taken out. It’s one of the most amazing things you could put in your body though…in Ayurvedic medicine it is considered a health elixer and has been revered in India for thousands of years. Another great substitute for cooking is Avocado oil (I don’t cook with Olive oil as it becomes damaging at higher heats).
Anyway, just thought I would mention…hope this was helpful.
Ghee, clarified butter, is not butter with the fat taken out. It is the oil that remains when everything else is taken out.
Do you have nutrition facts for this recipe? How much protein does it have per serving?
Wonderful! I added some cubed tempeh to the mix.
I am preparing this as I type for dinner this evening. Everything smells so delicious! I am finding, however, that my spaghetti squash is taking a lot longer to roast than 25 min. Though I have no doubt that this meal will be fantastic everything else is done and I sit here waiting on the squash.
Love love love the new site design Erin! It looks amazing. And goodness gracious this recipe. I have allllll the emoji heart eyes right now. Pinned! I loveee spaghetti squash. Lately my favorite way of making spaghetti squash is as a lasagna-style boat – baking it with marinara, cheese and herbs. Sooo good. But I need to give this a try too!
Caramelized onions are the ONLY way to eat onions in my opinion! The caramelization brings out the perfect comforting, buttery sweetness that i absolutely adore! That being said, I need to get my booty in the kitchen and try this recipe out.
Caramelized onions are so comforting to me! The last time I made them was for a recipe for mini salisbury steaks from Rachael Ray. No strange ingredients 😉