Notes: To double this recipe, use a larger pan and allow 10 to 15 extra minutes of cooking time. If making up to 3 days ahead, let caramelized onions cool, then chill airtight.
In a 3- to 4-quart pan over medium-high heat, frequently stir onions and garlic in oil until onions start to become limp; reduce heat to medium-low and stir frequently until onions are very soft and browned, 40 to 45 minutes. If onions start to stick to the pan, reduce heat further and stir in 2 tablespoons water. Add salt and pepper to taste.
Nutritional analysis per 3/4 cup.