I recently discussed the incredible Jerusalem Artichoke Veloute I had the pleasure of eating at Bar Boulud. It was one of those occasions when you enjoy something so much at a restaurant, that you just need to have it again. And again. And again. Making it yourself at home is a cheaper (and easier if you don’t live in NY) alternative, and I was so excited to see a recipe for Jerusalem Artichoke Soup with Sage Croutons in my personally autographed (I can’t help but brag) copy of The Cafe Boulud Cookbook. The version of the soup at Bar Boulud was garnished with crispy bacon and a watercress custard, while the version in the book boasts a topping of sage croutons and pancetta, diced from the thick pieces used to flavor the soup.
I can’t begin to tell you how amazing this soup is. It’s velvety and rich without tasting too heavy or creamy, with a tremendous depth of flavor developed from the pancetta, the various aromatics, and of course the star ingredient, the mildly sweet and nutty Jerusalem artichokes, or sunchokes. These tubers slightly resemble ginger root in their bumpy and irregular shape. They are not from Jerusalem, and are not even artichokes. These root vegetables are actually native to the eastern United States and are in season in the fall and winter (right now would be a good time to buy some!). When purchasing sunchokes, avoid those that are bruised, soft, or wrinkled. The skin should be rather smooth without sprouts, and the flesh beneath should be firm.
Jerusalem Artichoke Soup with Sage Croutons
(Adapted from Daniel Boulud’s Cafe Boulud Cookbook)
2 T. unsalted butter
3 to 4 oz. pancetta or slab bacon, cut into 3 chunks
1 large onion, peeled, trimmed, and thinly sliced
1 medium fennel bulb, trimmed and thinly sliced
1 medium leek, white and light green parts only, halved lengthwise, washed, and thinly sliced
1 celery stalk, peeled, trimmed, and thinly sliced
3 cloves garlic, finely chopped
Kosher salt and freshly ground black pepper
Bouquet garni (2 sprigs sage, 2 sprigs thyme, and 1 bay leaf, wrapped in a leek green and tied)
2 pounds Jerusalem artichokes (sunchokes), scrubbed and cut into 1/4-inch-thick slices
2 quarts unsalted chicken or vegetable stock, low-sodium chicken or vegetable broth, or water
1 small potato, peeled and diced
1/2 cup heavy cream
2 T. + 1 tsp. extra-virgin olive oil
2 slices bread, preferably country bread, crusts removed and cut into 1/4-inch dice (to make about 1 cup)
3 leaves sage, finely sliced
1 clove garlic, peeled and lightly crushed
Kosher salt and freshly ground black pepper
Melt the butter in a Dutch oven or large casserole over medium heat. Add the pancetta or bacon and cook, stirring occasionally, until it renders its fat, about 5 minutes.
Add the onion, fennel, leek, celery, and garlic, and season with salt and pepper. Toss in the bouquet garni and cook, stirring from time to time, for 5 minutes.
Add the artichokes and cook for 15 to 20 minutes more, stirring occasionally.
Pour in the stock or water, add the potato, and 1 1/2 teaspoons salt, and bring the mixture to a boil.
Lower the heat so that the soup simmers, and cook uncovered for 30 to 35 minutes, skimming the foam from the surface as needed. Spoon out the pieces of pancetta or bacon, cut them into a small dice and set them aside. Discard the bouquet garni.
Using a blender, hand-held immersion blender, or a food processor, and working in batches, puree the soup until it is very smooth. If desired, strain the soup through a fine-mesh sieve into a large saucepan, and taste for salt and pepper, adding seasoning as needed. Add the cream to the soup and bring to a boil, then lower the heat and keep the soup warm while you make the croutons. (The soup can be made ahead, cooled, poured into a container with a tight-fitting lid, and stored overnight in the refrigerator. Reheat over gentle heat before serving.)
For the croutons, warm 2 tablespooons of the oil in a small sauté pan or skillet over medium heat. Add the bread, sage, and garlic, season with salt and pepper, and sauté until the bread is crisp and golden brown. Discard the garlic and drain the croutons on paper towels. Save the crisp sage leaves to garnish the soup.
In the same skillet used to cook the croutons, drizzle 1 teaspoon more olive oil and heat over medium heat. Reheat and crisp up the diced pancetta or bacon for garnish. Remove from the skillet and drain on paper towels.
To serve, ladle the soup into warm bowls and top each serving with some of the crispy diced pancetta or bacon, a few croutons, and some strands of crisped sage.