Oven roasted portobello mushrooms and onions are the perfect addition to tacos, pizza, wraps and salads. Balsamic vinegar adds a flavor boost you will love! So easy- the veggies roast in the oven while you prep your meal.
This recipe originally published February 2014, now updated with new photos, step by step instructions and pro tips.
These oven roasted onions and mushrooms are so versatile! I like to roast a batch when I have time and then store them in the refrigerator to use throughout the week. Mushrooms and onions add tons of flavor to entrees, vegetables and snacks. These are also delicious added to tacos and as a pizza topping.
Roasting the mushrooms and onions with a splash of balsamic vinegar kicks the flavor up and makes these veggies perfect add ons to just about any recipe. Check out my Low Carb Steak Taco Bowl, Low Carb Mediterranean Chicken and Low Carb Fajita Lettuce Wrap for more ways to use roasted veggies.
Why this recipe works
- We are using a tasty combo of onions and mushrooms to add umami to almost any recipe we pair this with.
- A lower oven temp and longer roasting time just adds to the flavor.
- A great make ahead recipe.
Ingredients
- Onions- I used yellow onions but others can be used such as Vidalia, white or sweet onions.
- Mushrooms- You may use portobello or white varieties.
- Olive oil
- Balsamic Vinegar- choose your favorite brand
- Seasonings
Instructions
- Step 1: Add sliced onions and portobello mushrooms to a medium sized bowl.
- Step 2: Add remaining ingredients and stir to combine.
- Step 3: Roast in oven until tender and browned.
Expert tips
- Buy pre-sliced onions and baby bellas for convenience if desired.
- Use a foil-lined pan for easier clean up.
- Store in refrigerator up to 3 days.
Looking for more low carb recipe ideas? Check out my Low Carb Cheesesteak Stuffed Mushrooms, Low Carb Tomato Mushroom Pizza and Spinach Artichoke Dip!
Did you make this recipe? Be sure to leave your star rating below!
Recipe
Oven Portobello Mushrooms and Onions
Ingredients
- 2 medium Onions sliced
- 8 oz Mushrooms, portobello , sliced
- 2 Tablespoons Olive Oil
- 2 Tablespoons Balsamic Vinegar
- ½ Teaspoon Thyme
- ½ Teaspoon Black Pepper
- ¼ Teaspoon Sea Salt
Instructions
- Preheat oven to 375 degrees.
- Line a large baking sheet with foil and coat with nonstick spray. Set aside.
- In a large bowl, combine all ingredients, mixing well.
- Spread evenly onto baking sheet.
- Roast in oven for 45 minutes or until roasted and tender, stirring halfway through baking time.
- Use immediately or store in refrigerator for use later.
Notes
- Buy pre-sliced onions and mushrooms for convenience if desired.
- Use a foil-lined pan for easier clean up.
- Store in refrigerator up to 3 days.
Luisa Fijman
Very easy and flavorful. Full of nutrients.
Danielle
I’m doing the HCG diet and need recipes without oil. Do you have any suggestions? I love mushrooms and onions so I would love to be able to incorporate this recipe somehow without oil. Any suggestions?
Charlotte
Maybe try cooking in a non stick pan on low heat and cover the pan to retain moisture. Hope that helps!