Ingredients
- 2 tablespoons olive oil
- 1 tablespoon butter
- 2 large red onions, thinly sliced
- 1/4 cup white sugar
- 1 cup dry red wine
- 1/4 cup balsamic vinegar
- Salt to taste
Directions
Heat olive oil and butter in a large skillet over medium heat; cook and stir onions and sugar in hot oil until onions start to caramelize, about 15 minutes. Stir red wine and balsamic vinegar into onion mixture and bring to a boil. Reduce heat to medium-low and simmer until liquid is evaporated, 15 to 20 minutes more. Season with salt.
