Ingredients
Method
- Heat butter in a skillet over medium heat. Add in the onion.
- After 10 minutes, add balsamic vinegar and brown sugar. Cook, stir and scrape the brown bits from time to time for 20-30 minutes more, until onion get a rich brown color. (I like mine to have a little bit of crispy black bits on it as well)
- Transfer caramelized onion in a bowl and set aside (you can keep it refrigerated in an airtight container for one week).