These Caramelized Mushrooms and Onions are full of sweet, earthy flavor, and are made with just a few ingredients. This simple recipe makes for a perfect side dish for a variety of main courses. Though it takes a few minutes from start to finish, the extra time is worth the wait!
If you love mushrooms and onions, and you need a versatile side dish, you will love this tasty topping.
Use it on burgers, as the perfect topping for this air fryer ribeye or these air fryer short ribs, and more! It's absolutely packed with savory flavor, and a little bit of sweetness, what's not to love?
❤️Why we love this recipe
- Made with simple ingredients - Made with pantry staples and a few items, you likely have nearly everything on hand already. Anything you still need can be found at nearly any grocery store.
- The perfect versatile side dish - Whether you're making a steak dinner, burgers, pork chops, lamb, or chicken, these tasty morsels will level up your next meal.
- Easy recipe - All you need is a little bit of time to allow the caramelization process to take place, and make your mushrooms and onions incredibly tasty. Other than that, there's not much to this recipe.
- Naturally gluten free - Made with whole foods, everything in this recipe is naturally gluten-free, so there's no need to worry.
- Tons of rich flavor - The slow cooking process necessary for this recipe creates an incredible deep flavor as the mushrooms and onions release natural sugars and caramelize.
Here are the ingredients you'll need for this recipe. Find the list of substitutions and variations below.
- Sweet onions - We generally opt for yellow onions, or Vidalia onions, as they are the sweetest.
- Mushrooms - We used a mixture of shiitake mushrooms (our favorite) and baby bella mushrooms. You can use baby bella or white button mushrooms, as these are commonly available and very tasty.
- Olive oil & unsalted butter - We like to use a mixture of both to help keep the mushrooms and onions from sticking to the pan. You can of course just use one or the other.
- Kosher salt and black pepper
- Chicken broth
- Balsamic vinegar & Worcestershire sauce - Technically optional, but both items add a ton of flavor.
- Honey - Optional, but honey adds a ton of flavor and brings out the natural sugars and sweetness in the onions.
- Add fresh parsley or thyme to garnish (optional)
Full quantities and nutritional information can be found in the recipe card.
📋Substitutions & variations
- Swap the deglazing liquid - You can use white wine, beef broth, or vegetable stock in place of chicken stock.
- Low carb - Omit the honey.
- Garlicky - Add lots of garlic!
- Herbed - Add savory herbs like sage, more thyme, and rosemary for lots of herbaceous flavors.
- Vegan - Swap the chicken broth for vegetable broth, use vegan butter instead of regular butter, use maple syrup instead of honey, and use soy sauce instead of Worcestershire sauce.
- Spicy - Add red pepper flakes.
- Swap red onions for yellow onions - If that's all you have on hand, red onions will work just fine!
- Clean mushrooms with a damp towel or paper towel and wipe off any dirt.
- Cut mushrooms and onions into thin slices, about ¼ inch thick.
- Finely mince garlic.
- Preheat a large skillet (a 12" inch or larger cast iron skillet or enameled cast iron skillet) over medium heat.
Melt butter in the hot pan over low heat. Add olive oil and garlic. Cook until garlic is fragrant, about 1 minute, moving often to prevent burning. (Image 1)
Increase the temperature to medium heat. Add mushrooms and onions, and cook without touching them for about 5 minutes. (Image 2) After about 5 minutes, season with salt, pepper, and fresh thyme (optional). (Image 3)
Add chicken broth, Worcestershire sauce, balsamic vinegar, and honey to deglaze the pan. Toss to combine, and scrape the bottom of the pan to scrape up any browned bits. Increase to medium-high heat. (Image 4)
Stir every 5 minutes or so until there is no excess liquid in the pan and the mushrooms and onions have nice browned edges and everything is golden brown. This will take roughly 40-50 minutes. (Image 5)
✨Pro tip - Cooking time will vary a little, as it truly depends on how long it takes for the liquid in the pan to evaporate.
That's it! Serve and enjoy! We love to eat it with this air fryer ribeye.
✨Tips & tricks
- Don't overcrowd the pan. Use a large skillet to make sure the ingredients make as much contact with the pan as possible. This will encourage caramelization. The mushrooms and onions will release water, however, so they will end up taking up less room than at the beginning of cooking!
- Don't cover the pan. This will cause the vegetables to steam, rather than caramelize and you won't get a nice crispy edge.
- Don't burn the garlic. If you burn the garlic, you have to start over, as it will add a bitter taste to the dish.
- Patience is key. The key to this recipe is time! There simply just isn't the option to rush it. The long cooking time creates amazing caramelization in the pan.
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💭Frequently asked questions
Store leftovers in an airtight container in the fridge for up to 5 days. Reheat gently in the microwave or on the stovetop in a skillet with a bit of broth or water.
To freeze, allow the mushrooms and onions to cool at room temperature, then transfer to a freezer safe bag. Store in the freezer for 2-3 months. Thaw overnight in the fridge.
More Recipes To Try
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Caramelized Onions and Mushrooms
- 4 tablespoons unsalted butter
- 2 tablespoons olive oil
- 6 cloves garlic, minced
- 16 ounces mushrooms, sliced (we used a mixture of baby Bella and shiitake)
- 4 medium yellow onions, thinly sliced
- 2 teaspoons kosher salt (to taste, added gradually)
- 2 teaspoons thyme, fresh (could use 1 teaspoon of dried)
- ½ teaspoon coarse black pepper (or to taste)
- 1 tablespoon honey (to taste)
- 2 tablespoons Worcestershire sauce
- 2 tablespoons balsamic vinegar
- 4 ounces chicken broth (½ cup, could use white wine, beef, or vegetable broth)
- Add butter and olive oil to a dutch oven to melt over low heat. Once melted, add garlic and saute until fragrant, about 1 minute.
- Increase to medium heat. Add in onions and mushrooms. Allow to cook down for about 5 minutes, and don't touch them at this time.
- Season with salt, pepper, and thyme. Increase the heat to medium-high. Add in the Worcestershire sauce, honey, balsamic vinegar, and chicken broth. Toss to combine again, and stir every 5 minutes or so until there is no excess liquid in the pan and the mushrooms and onions have nice browned edges. This will take 45-50 minutes. Adjust seasonings to taste, and enjoy!
- Store in an airtight container in the fridge for up to 5 days.
- Make sure mushrooms are dried really well before cooking, as mushrooms are very absorbent and excess water will make it harder to achieve a nice golden brown crust.
- We do recommend using yellow or Vidalia onions for the sweetest flavor. Red onions can be used but they will give a slightly more bitter flavor.
- Chicken broth can also be substituted with beef broth (for a beefier flavor to accompany beef dishes), vegetable broth for vegetarians, or even white wine.
- Sweeten to taste. Vidalia onions (if used) are particularly sweet, so you may require less honey.