Ingredients
2 tablespoons (1/4 stick) butter
2 tablespoons olive oil
2 1/2 pounds red onions (about 4 medium), halved, thinly sliced
2 teaspoons balsamic vinegar
1/2 teaspoon coarse kosher salt
1/4 teaspoon ground black pepper
1/4 cup chopped fresh chives
Preparation
Melt butter with olive oil in large nonstick skillet over medium heat. Add onions and cook until deep golden brown, stirring frequently, about 30 minutes. Stir in vinegar, 1/2 teaspoon salt, and 1/4 teaspoon pepper. Remove from heat. (Can be prepared 1 day ahead. Cover and refrigerate. Rewarm over medium heat before serving.) Stir in chives.
