Easy roasted red onions are the perfect way to meal prep. Bake in the oven for use in your favorite lunch bowl, as a taco topping, or as a standalone side dish. This roasted red onion recipe is easy to reheat and can be served warmed, chilled, or at room temperature.
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We have been on a roasting streak in the Peel house lately. Maybe it is the colder than normal weather. You can check out our most recent slow-roasted tomatoes and our roasted garlic to see what I am talking about. Serious goodness!
If you find raw red onions too harsh then these oven roasted red onions are for you. Roasting the red onions removes the spiciness allowing the sweetness to shine.
How to Make Perfectly Roasted Red Onions
This is a very simple and straightforward recipe. Roasted onions are easy to make in the oven using a neutral oil like olive or filtered coconut and salt and pepper. But you can add additional seasonings like lemon zest, hearty fresh herbs (we like thyme), or even spicy dried chilis.
Prep the Baking Sheet- Line a baking sheet with parchment paper to prevent sticking, you can also use foil. Alternately you can oil the baking sheet but if your onions are high in sugar they may still stick even with the oil making Clean up a pain.
Prep the Onions- Peel the papery layers off your onions. Your red onions should be sliced into ½ thick slices. Thinner sliced onions may cook faster, but they also get gummy so stick with the thicker slice. Layout the red onions on the baking sheet and lightly brush with oil and season with salt and pepper. Add any additional seasonings at this time.
Oven Bake- Start by preheating the oven to 400 F degrees. Roast until caramelized, about 15 to 20 minutes. Flip halfway through for even caramelization.
How to Make Balsamic Red Onions
This is a special variation of this recipe that we love to make but I didn't think it was different enough to warrant its own recipe and post.
To make balsamic and thyme roasted onions mix in the leaves of 4 fresh thyme sprigs (or ½ teaspoon of dried thyme) and 2 tablespoons of balsamic vinegar in with the 2 tablespoons of oil.
Brush (or drizzle) on the onions before baking. Flip halfway through the baking (stil 15 to 20 minutes total) and brush (or drizzle) on an additional 2 tablespoons of balsamic vinegar.
How to Use Roasted Onions
We use this roasted red onion recipe as a standalone side dish and in some of our favorite dishes.
- On a roasted veggie sandwich, or really any sandwich
- As a side dish, balsamic style
- Chopped up with fresh herbs and mixed into cream cheese for a roasted red onion bagel spread
- On top of our favorite Wagyu burgers or our blackened chicken sandwich
- On tacos, we really like these paired with our citrus shredded beef
- Chopped and mixed with refried beans or cheese for vegetarian enchiladas
- On a vegan antipasto platter
Let us know in the comments how you plan to serve your roasted red onions!
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Roasted Red Onions
- Preheat oven to 400 F degrees. Line rimmed baking sheet with parchment paper or lightly brush with oil.
- Cut onions into ½ inch slices. Arrange onions on a baking sheet. Brush lightly with oil and season with salt and pepper.
- Roast until caramelized and tender, 15 to 20 minutes. Flipping once halfway through.