plus 2 tablespoons olive oil
large shallots, thinly sliced
kosher salt and black pepper
white wine vinegar
large heads frisée, torn into bite-size pieces (about 12 cups)
- Heat 2 tablespoons of the oil in a medium skillet over medium heat. Add the shallots and ½ teaspoon salt and cook, stirring often, until softened, 8 to 10 minutes. Add the vinegar, sugar, the remaining ⅓ cup of oil, ½ teaspoon salt, and ¼ teaspoon pepper and cook, stirring, until heated through, 1 minute.
- In a large bowl, combine the frisée and warm vinaigrette and toss to coat.