Balsamic Roasted Red Onions with Thyme

Balsamic Roasted Red Onions with Thyme

Sometimes I think I would probably be fine just having condiments for dinner. A few pickled grapes, maybe some chive Hollandaise licked off a spoon. And these. A whole bowl of these, please.

I wanted something a little sweet and tart to go along with our Grilled Steak with Blue Cheese and Chive Compound Butter and as soon as I saw Ina Garten’s recipe for Balsamic Onions, I knew I wanted to do a version of it. I added thyme because I love their flavor with anything roasted, though rosemary would also be great. I also increased the cooking time by quite a bit because I wanted the onions to be quite soft and caramelized, as opposed to still crunchy.

Steak with Blue Cheese Chive Butter & Balsamic Red Onions

Balsamic Roasted Red Onions with Thyme
Don’t slice the onions paper thin or they’ll get mushy. 1/4 inch is perfect.
Balsamic Roasted Red Onions with Thyme
Whole thyme sprigs; pretty for pictures, annoying to pick out later. Pull yours off the stem.
Balsamic Roasted Red Onions with Thyme
Toss around once or twice during roasting so they cook evenly.

As the onions roast they become sweet, tender and just a little bit tart. They were insanely good with the steak, but they would be equally delicious on top of burgers, alongside grilled chicken or pork, on tacos. Even folded into an omelette with a little goat cheese.

The vinegar really mellows as it cooks and becomes almost syrupy so a little splash of raw balsamic at the end perks up the flavor.

Balsamic Roasted Red Onions with Thyme
Gorgeous and delicious.
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Balsamic Roasted Red Onions with Thyme

Prep Time5 minutes
Cook Time30 minutes
Total Time35 minutes
Servings: 6 -8 servings
Author: Emily Clifton - Nerds with Knives (Adapted from Ina Garten)


  • 3 large red onions about 2 lbs / .9 kilos
  • 1/4 cup plus 2 tablespoons balsamic vinegar 60 mL plus 30 mL
  • 1/4 cup extra virgin olive oil 60 mL
  • 2 teaspoons fresh thyme about 8 sprigs or 1/2 tsp dried
  • 1/2 teaspoon course kosher salt
  • 1/2 teaspoon freshly ground black pepper


  • Preheat the oven to 375ºF / 190ºC
  • Cut the onions in half vertically and then into 1/4 inch thick slices (not paper thin or they’ll get mushy). Place on a baking sheet and toss with olive oil, thyme, salt, pepper and 1/4 cup balsamic vinegar.
  • Bake on the middle rack for 30 minutes, turning once or twice, until the onions are soft and lightly caramelized. Remove from the oven, and while they’re still hot, pour over 2 more tablespoons balsamic vinegar. Toss to coat. Can be served warm or at room temperature.
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