Roasted red onions are a simple yet flavorful side dish, with an incredible sweetness that pairs perfectly with grilled or roasted meats. While onions often play a supporting role in recipes, here they shine on their own. Roasted to perfection and finished with a touch of balsamic vinegar for a rich, savory sweetness. Give this humble ingredient the spotlight it deserves—you’ll be amazed at true depth of flavor.
The first time I made these, the edges of the onions turned a deep brown, caramelized from the heat of the oven. Roasting turns a normally pungent, eye-watering, mascara-smearing onion into something as sweet as candy. Yes, I see you looking at me with doubt and skepticism. Trust me. You must make these roasted red onions.
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Why You'll Like This Recipe
- Simple ingredients, simple recipe.
- Onions are really good for you!
- Easy to make, great rich flavor.
- Great way to add more vegetables to your menu.
Another terrific recipe with balsamic is these roasted balsamic glaze Brussels sprouts.
Recipe Ingredients
- Onions: Red onions.
- Oil: Extra virgin olive oil.
- Garlic: Use granulated garlic. Fresh garlic burns easily.
- Herbs: Fresh chopped thyme leaves
- Vinegar: Balsamic vinegar or Balsamic glaze. It's a terrific flavor enhancer.
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If you'd like to make your own Balsamic glaze, it's easy. Find the instructions in this Balsamic strawberries post.
Chef's nutrition tip: Red onions are good for you! Onions are rich in sulfur-containing compounds that give them both their pungent odor and much of their health benefits. Onions are also a good source of quercetin, a powerful antioxidant and natural antihistamine. Read more about the health benefits of onions here and try this roasted red onion recipe.
Recipe Instructions
Pre-heat the oven to 400°F. Ready a large glass or stoneware baking dish, about 10″x13″.
- Step 1: Peel onions and cut in half from the root to stem end. Lay each half flat and cut the halves into 6 wedges.
- Step 2: Add onion wedges to the baking dish and toss with oil, then sprinkle with salt, pepper and garlic.
- Step 3: Roast onions uncovered for about 40 minutes, or until they are very soft and the edges are very brown. Remove dish from the oven, toss with the Balsamic and sprinkle with thyme leaves.
Serving Suggestions
- Serve as a side dish along roast chicken
- Pile on a grilled steak or steak salad
- Pile them on asparagus for a double vegetable side
- Add to a salad, either warm or cold
- Pile on quinoa or rice with other vegetables for a delicious veggie bowl
📖 Recipe
Roasted Red Onions with Balsamic
Equipment
- glass or ceramic baking casserole dish approximately 10x13
Ingredients
- 2 large red onions about 1 ½ pounds
- 3 tablespoons olive oil
- ½ teaspoon sea salt
- ¼ teaspoon granulated garlic
- ¼ teaspoon ground black pepper
- 1 ½ tablespoons fresh chopped thyme leaves
- 1-2 tablespoons Balsamic vinegar or syrup
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Instructions
- Pre-heat the oven to 400°F. Ready a large glass or stoneware baking dish, about 10″x13″. Cut the onions in half from the top to bottom, from root to stem end. Trim the root and stem ends flat. Peel off the papery skin, then lay each half flat on a cutting board and cut the halves into 6 wedges.
- Add onion wedges to the baking dish and toss with oil, then sprinkle with salt, pepper and garlic. Roast onions uncovered for about 40 minutes, or until they are very soft and the edges are very brown. Remove dish from the oven, toss with the Balsamic and sprinkle with thyme leaves. See note below on Balsamic.
Porsche Guy says
I made these for serving with a grilled steak and they were great. Really surprised at the sweet flavor. Love Balsamic. Thanks for an unexpected tasty recipe.