Name: Roasted Red Onions
Prep time: 5 min
Cook time: 20 min
Total time: 20 min
Ingredients: 2 red onions; 2 tablespoons olive oil or coconut oil; kosher salt and pepper

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Roasted onions make for an easy winter side dish (or condiment?). Dress them up with herbs and garlic or keep them simple with salt and pepper. You just need a sheet pan and 20 minutes to caramelize red onions in the oven. Try them for meal prep!

A plate of roasted red onions garnished with herbs and spices rests elegantly on a pink napkin.

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I use this roasted red onion recipe as a standalone side dish but you can try this recipe for topping a roasted veggie sandwich, or really any sandwich! My favorite fancy burgers or my blackened chicken sandwich.

📖Why My Recipe Works

Roasting red onions reduces their sharpness and allows the sweetness to shine. If you find raw red onions too harsh, then these baked red onions are for you!
Add additional flavors like lemon zest, hearty fresh herbs (I like thyme), or even spicy dried chilis.

🧾Ingredient Notes

Red Onions- This recipe works with any type of onion not just red onions. Cut the onions into a wedge shape or rings.
Oil- Roasted onions are easy to make in the oven using a neutral oil like olive oil, filtered coconut, or avocado oil. And yes, even melted butter.
Don't forget to pick up additional items for bigger flavor.

Roasted red onions, olive oil, salt, and pepper adorn the kitchen counter. Optional garlic, balsamic vinegar, and herbs are waiting to join the mix.

⏲️How to Make Roasted Red Onions

Start by preheating the oven to 400 F degrees.

Sliced red onion and onion skin on a wooden cutting board, ready to become delicious roasted red onions.

Don't cut less than a ¼ inch thick or they will burn.

Four sliced red onions, perfectly seasoned with pepper and ready to be roasted, sit on parchment paper atop a baking tray.

Parchement is optional. Lay the onion slices in a single layer and brush both sides with oil. Season as desired.

Flip the onions halfway through so that they roast evenly. Let the onions roast until tender and caramelized, around 15 to 20 minutes. You'll know they're done when they're fork tender and the edges are browned.

How to Make Balsamic Roasted Onions

This is a special variation of this recipe that I love to make, but I didn't think it was different enough to warrant its own recipe.

To make, mix the leaves of 4 fresh thyme sprigs (or ½ teaspoon of dried thyme) with 2 tablespoons each of balsamic vinegar and olive oil.
Brush (or drizzle) the onions before baking. Flip halfway through the baking (still 15 to 20 minutes total) and brush (or drizzle) on an additional 2 tablespoons of balsamic vinegar.

How to Use Roasted Onions

As a side dish, I recommend the balsamic style.

For breakfast, mix it into scrambled eggs or my broccolini frittata recipe. Or chop up the onions with fresh herbs and mix into cream cheese for a roasted red onion bagel spread.

On tacos, I really like these onions as a condiment paired with my citrus-shredded beef, pollo asado, or BBQ shredded beef.

Chopped and mixed with refried beans and cheese for vegetarian bean tacos.

A plate of roasted red onion slices garnished with fresh herbs sits invitingly on the table, accompanied by a pink napkin and a fork.

👩🏻‍🍳 Expert Tip

Once out of the oven, let the onions sit for a couple of minutes. This gives the sugars time to settle, enhancing their sweet, rich flavor.

Did you enjoy making this recipe? Show it some love with ⭐⭐⭐⭐⭐ and leave a comment! Hungry for more? Get more flavorful recipes!

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