Add 1 tablespoon olive oil to a hot pan. Add chopped onion and cook on low heat for about 35 minutes, or until onions are caramelized. Add balsamic vinegar to deglaze the pan. Add salt.
Add 1 tablespoon olive oil to a hot pan. Add chopped onion and cook on low heat for about 35 minutes, or until onions are caramelized. Add balsamic vinegar to deglaze the pan. Add salt.