Roasted Onions with Lemon

  • Total: 1 hr 30 min
  • Prep: 30 min
  • Cook: 1 hr
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1/2 cup extra-virgin olive oil

2 large sprigs rosemary, leaves stripped

1 bunch thyme

6 red onions, halved through the root end (unpeeled)

3 white onions, quartered through the root end (unpeeled)

Kosher salt and freshly ground pepper

2 lemons

2 tablespoons vegetable oil

2 tablespoons apple cider vinegar

1 tablespoon dijon mustard


  1. Preheat the oven to 400 degrees F. Drizzle 2 tablespoons olive oil on a rimmed baking sheet. Scatter the rosemary leaves and thyme sprigs on the baking sheet. Season the onions with salt and pepper; arrange on top of the herbs, cut-side down.
  2. Remove 4 wide strips zest from the lemons using a vegetable peeler; set aside. Cut each lemon in half and remove any seeds; add to the baking sheet cut-side down. Roast until the onions are tender and the skins are slightly charred, about 1 hour.
  3. Meanwhile, make the vinaigrette: Combine the vegetable oil, vinegar, mustard and 1/2 teaspoon salt in a blender. With the motor running, gradually drizzle in the remaining 6 tablespoons olive oil and 2 tablespoons water until emulsified. Transfer to a small bowl; add the lemon zest and season with salt and pepper. Let steep at least 30 minutes; remove the lemon zest.
  4. Remove and discard the skins from the onions. Arrange the onions, lemons and herbs on a platter and drizzle with the vinaigrette just before serving. (The roasted onions and vinaigrette can be made up to 4 hours ahead. Serve at room temperature.)
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