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Sautéed Spinach, Mushrooms, and Caramelized Onions - a delicious side dish recipe that will go great with lots of main dishes. Serve it with pasta, grilled meats, or seafood. You can also make it instead of gravy for the holidays (Thanksgiving and Christmas).
The flavors of mushrooms, spinach, caramelized onions, garlic, and Parmesan cheese mingle really well in this meatless recipe. It's quite versatile: you can eat it as-is, especially if you're craving some good-tasting, creamy vegetables. You can serve it alongside some pasta, ravioli, or tortellini. It is also great with grilled steak, pork, or chicken.
For me, personally, this delicious Sautéed Spinach with Mushrooms and Caramelized Onions is a favorite side dish for grilled meats. The recipe is flexible: you can exclude the creamy sauce and Parmesan cheese if you're trying to eat a little bit healthier (even though the recipe doesn't use much of either). You can also omit onions if you don't like them, or, if you don't have time to caramelize them, saute them.
Sautéed Spinach, Mushrooms, and Caramelized Onions
Ingredients
Caramelized onions
- 1 tablespoon olive oil
- 3 yellow onions , large, sliced
- ¼ teaspoon salt
- 1 tablespoon balsamic vinegar
Other ingredients
- 1 tablespoon olive oil
- 10 oz mushrooms , sliced (I used button mushrooms)
- 6 oz spinach
- 1 cup half-and-half
- 1 cup Parmesan cheese , shredded
- ¼ teaspoon salt
Instructions
How to caramelize onions:
- Heat 1 tablespoon olive oil on medium-high heat in a large skillet. Add sliced onions and cook on high heat for about 10 minutes, constantly stirring with the spatula.
- The onions should start to brown, but without burning.
- Reduce heat to medium and continue cooking onions for 10 more minutes, continuing to stir, as onions brown even more without burning. At this point add a pinch of salt over onions.
- Continue cooking for 10 more minutes on medium or low heat, stirring occasionally to make sure onions don’t stick to the bottom of the pan or burn.
- In total, you should have cooked onions for 30 minutes.
- Remove the skillet from heat and sprinkle the onions with a small amount of balsamic vinegar to deglaze the pan.
- Using a spatula, stir the onions, scraping the bottom of the pan and coating onions with a pinch of balsamic vinegar you just added. Remove caramelized onions to a plate.
How to cook mushrooms and spinach:
- Heat 1 tablespoon olive oil in the same skillet on medium heat. Add sliced mushrooms. Sprinkle with a pinch of salt.
- Cook mushrooms for about 5 minutes, occasionally stirring, until mushrooms are soft.
- Add fresh spinach to the skillet and stir on low heat just until spinach starts to wilt.
How to make a creamy sauce
- Add half-and-half to the mushroom and spinach mixture and bring to a quick boil. Immediately reduce to simmer.
- Add ⅔ cup of shredded Parmesan cheese and ¼ teaspoon salt. Keep stirring while the sauce simmers until the cheese melts.
- Add caramelized onions back to the skillet with the pasta sauce.
- If the sauce is too thick, add a small amount of half-and-half to thin it out. If it is too thin, add a small amount of shredded Parmesan cheese, and stir it in, while the sauce simmers.
Notes
Nutrition
Nutrition Disclaimer:
The nutritional information on this website is only an estimate and is provided for convenience and as a courtesy only. The accuracy of the nutritional information for any recipe on this site is not guaranteed. It should not be used as a substitute for a professional nutritionist’s advice.
Can this Sauce be frozen
Anne, I don't recommed freezing this because creamy sauce does tend to lose texture after it's frozen and then thawed. But, since there is no cheese in this, you can try. But be very careful reheating it. Let it thaw overnight, and reheat on very low heat so that the sauce doesn't separate into grease.
Loved it! Very easy to prepare, and I also added zucchini to the recipe.
Gail, glad you enjoyed this recipe! Love the addition of extra veggie! 🙂
I made this and added bacon pieces and roasted pecans!
I love your add-ins! 🙂
I made this recipe the other day and served it with a 4-cheese tortellini. My fiancé said it’s one of his favorite recipes I’ve ever made. He said it’s in the top 3! I loved it, as well! I honestly never realized how time consuming caramelized onions are to make, though! What a yummy recipe and definitely worth the time!!
Nicole, I am so glad you took the time to make this recipe (I agree caramelized onions do require some time investment) and loved it! ❤️ Thank you for your rave review and the 5-star rating! ❤️
I love this, its such a good base for other ingredients. I had some baked chicken and andoullie sausage that I added and put this over couscous. I think about any green veggie would be great and it would be great over pasta, wild or regular rice or mushed potatoes.Thank you
Excellent!!! Love this as a side to grilled steak (snuck in 1 clove of garlic minced to the spinach mushroom mix)
Sauce was a little thing despite using almost 3x spinach, 2x onions and 1.5x mushrooms. Added as much cheese as I reasonably could. Next time I will start with 1/2 cup of half and half. Taste was great.
David, glad you liked the flavor! Thank you for trying this recipe!
Could you bake this in a tart shell? If so, what could you do to keep the shell from getting too soggy while cooking in the oven. I'm thinking of this for a Thanksgiving side dish.
Michele - this will make a delicious filling for a tart shell - love that idea! ❤️ In that case, you can probably use as little as 1/4 cup of half-and-half but keep the amount of Parmesan cheese the same (1 cup). 1/4 cup of half-and-half should be just enough to melt the cheese into a thick texture.
"Sauce was a little THIN". Where is spell check when you need it
Just made this recipe and love it. Was looking for a mushroom sauce to add lump crab to and this worked scrumptiously.
Tammy, I love that you served this with lump crab - what a delicious combination! ❤️
Hi.
Looking forward to trying your recipes. What is half and half?
Sharon, half-and-half is a US milk product. 1 cup of half-and-half is 1/2 cup of regular milk + 1/2 cup of heavy cream (the fat content of heavy cream is usually about 36%).
This was super good and my husband loved it . It’s a great recipe. Thanks for sharing it . It will be on the repeat list !
Karen, I am so happy you've added this recipe to your rotation. Thank you for the glowing review and 5 stars! 🙂
Hi Julia,
I recently discovered your album and I am loving the recipes! I just made this sauce tonight over Rotini and my husband and I love it! It was so easy to make and was super delicious and healthier than my normal fast food. Thank you
Debbie, I am so glad you found my food blog! Thank you for taking the time to share such a positive comment! 🙂 I hope you'll find other recipes you like.
This was a wonderful recipe! I made it just like you said and it turned out perfectly. We are mostly vegan, so I didn't add the cream sauce and it certainly didn't need anything else. Thank you!
Shirley, I am so glad the recipe was a success! This tastes delicious even without the cream, for sure!
This recipe is insanely good! I make it regularly. I made a vegan version where I used oat milk and vegan parmesan, it's not quite as good as the original (sorry vegans) but still really good! I always have it with tagliatelle - sometimes homemade which is the best! People always ask me for this recipe and my family and friends all make it on the regs. Thanks Julia
Amber, your comment made my day! So happy to hear you make this recipe regularly and enjoy it! Love that you serve this over pasta - sounds delish!
This was really good, both my husband and I enjoyed and looking forward to adding this to many more dinners to come.
AMAZING!!! Prepared tonight with the cream sauce and it was layered with flavor and devoured.
I stuffed spaghetti squash with this.. I also added turkey bacon in mixture. Baked in over with shredded motzerella cheese and Monterey jack. Was so delicious.