Use these caramelized onions to make chef Andy D'Amico's amazing Five Napkin Burger.
Heat olive oil in a large skillet over low heat. Add onions and 1 teaspoon salt and cook, stirring occasionally, until onions are soft and golden, 45 to 60 minutes.
Increase heat to medium-low and continue cooking until lightly browned and caramelized; season with salt and 1/4 teaspoon pepper. Remove from heat.