Ingredients
1/2 cup extra-virgin olive oil
2 pounds onions, thinly sliced
1/2 cup water (or low-sodium chicken stock)
1 tablespoon balsamic vinegar
1 teaspoon sugar
Coarse salt
Preparation
In a medium pot, heat oil over medium heat and cook onions, covered, stirring occasionally until translucent, about 15 minutes. Add water, vinegar, and sugar and cook uncovered, stirring, until onions are caramelized, about 30 minutes more. Season with salt. Let cool completely.
