Caramelized Onions

Name: Caramelized Onions
Prep time: 5 min
Cook time: 55 min
Total time: 1 h
Yield: 6
Ingredients: Ingredients; 4 large yellow onions (about 3 lbs), thinly sliced; 3 tablespoons butter; 2 tablespoons olive oil; 1 teaspoon kosher salt; 1/2 teaspoon black pepper; 1 tablespoon brown sugar (optional, for deeper color); 2 tablespoons balsamic vinegar (optional); 1/4 cup dry white wine or beef broth (optional, for deglazing); Fresh thyme sprigs (optional)