Soup: comfort in a bowl. In the winter, we eat soup at least once a day. Most of the time, we crave vegetable soups, full of chunky bits of goodness, with something to thicken the broth up: it can be a crushed potato, beans, or a roux. The soup below, thickened with beaten eggs, is a play on the spinach soup my husband grew up eating at home: his father Attilio cooked down spinach in broth until silky soft, then stirred in plenty of Parmigiano and beaten eggs just before serving. Here we use escarole instead of spinach, top it with crispy Pancetta for texture and meaty depth, add a squeeze of lemon juice to the eggs to lighten the flavor, and stir in pesto at the very end to brighten things up. Serve this soup with bread and salad, and you have a memorable meal fit for a chilly day indoors.
For the pesto:
- 1/2 cup packed basil leaves (about 1/2 large bunch)
- 1 garlic clove
- 1 ounce (1/4 cup) freshly grated Parmigiano-Reggiano
- 1/4 teaspoon sea salt
- 1 tablespoon extra-virgin olive oil
For the soup:
- 1 ounce Pancetta, defatted and cut into 1/4-inch dice
- 1 teaspoon extra-virgin olive oil
- 1/2 medium yellow onion, minced
- 2 garlic cloves, minced
- water as needed
- 1 head escarole (about 1 pound), washed thoroughly and chopped
- 2 cups chicken broth
- 1 teaspoon sea salt
- 1/4 teaspoon freshly ground black pepper
- 2 large eggs
- 1 teaspoon lemon juice
Make the pesto: Place all the ingredients in a food processor and process to a fine paste; there may be some little basil strands here and there, because there is very little oil in this pesto, but that is fine. The purpose of this pesto is to lend flavor to the soup, not to make the soup creamy in texture, so a semi-chunky texture is fine. Remove to a bowl and lay plastic wrap directly on top of the pesto to prevent darkening. This can be done up to 2 hours before serving. Hold at room temperature until needed.
Make the soup: Place the Pancetta in a 2-quart pot. Set over medium heat and cook until the Pancetta is crispy and lightly golden, about 3 minutes; remove with a slotted spoon to a bowl.
Place the olive oil, onion, and garlic in the same pot in which you cooked the Pancetta. Set over medium heat and cover. Cook for 5 minutes, stirring often and adding a bit of water if needed to prevent scorching, until the onion becomes translucent. Add the escarole and cover the pot with a tight-fitting lid. Cook, stirring often, until wilted and collapsed, about 8 minutes. Add the broth, season with 3/4 teaspoon of the salt and 1/8 teaspoon of the pepper, and bring to a boil. Lower the heat to medium-low and cook, covered, for 15 minutes, or until the escarole is silky and the soup smells rich and deep. The soup can be made up to this point 2 hours before serving and held at room temperature. Reheat when needed to the boiling point.
When you are ready to serve, beat the eggs with the lemon juice, the remaining 1/4 teaspoon of salt, and the remaining 1/8 teaspoon of pepper. Return the soup to a boil. Pour in the eggs and let sit, undisturbed, until the eggs set, about 1 to 2 minutes. Stir gently once or twice, being careful to leave the eggs in large fluffy clouds, swirl in the pesto, and adjust the seasoning as needed. Serve hot, topped with the crispy Pancetta.