Onion soup is made throughout Italy. Traditionally, a pot of onion soup would simmer gently on the stove all day. If eaten for lunch, it would be brothy. Later in the day, after the soup had cooked down, the consistency is more stewlike. How long you cook this soup is up to you!
Preparation time: 15 minutes
Cooking time: 2 hours, 30 minutes
Yield: 4 to 6 servings
1/4 cup olive oil
6 medium red onions
6 cloves garlic
1 celery stalk
1 medium carrot
8 slices of pancetta or bacon (about 4 ounces)
1 teaspoon crushed red pepper flakes
1 tablespoon red wine vinegar
1 cup white wine
Salt and pepper to taste
2 1/2 quarts water or vegetable stock
1/4 cup grated Parmigiano-Reggiano cheese (optional)
Peel the onions, cut them in half, and then slice them 1/8- to 1/4-inch thick.
Peel and thinly slice the garlic cloves.
Chop the celery stalk and carrot.
Finely chop the pancetta or bacon.
In a large soup pot, heat the olive oil over medium heat.
Add the onions, garlic, celery, carrot, pancetta, and red pepper flakes.
Cook for 10 to 12 minutes, stirring occasionally, until the onions are soft.
Add the vinegar and wine.
Cook until the liquid has almost completely evaporated, about 5 minutes.
Season with salt and pepper.
Add the water or broth and bring to a boil.
Reduce the heat and simmer, loosely covered, for 2 hours (or longer, if you want).
The onions will have melted after 2 hours.
Adjust the flavor with salt and pepper, if necessary.
Sprinkle with Parmigiano-Reggiano cheese before serving, if you want.
Ladle into large soup bowls.