Chestnut and Celery Root Soup with Sage Croutons and Bacon

Cut off and discard the crusts from the bread. Cut the bread into 1/2-inch cubes; you should have about 4 cups bread cubes.

In a large fry pan over medium-low heat, melt 1 Tbs. of the butter with the olive oil. Add the garlic and 2 tsp. of the sage and cook gently until the garlic is light golden brown, about 5 minutes. Remove and discard the garlic. Increase the heat to medium, add 1/4 tsp. salt and the bread cubes, and stir to coat the cubes with the flavored oil. Cook, stirring and tossing often, until the croutons are crisp and toasted, 10 to 12 minutes. Transfer to a bowl.

In a large Dutch oven or other heavy pot over medium heat, cook the bacon until crisp, about 8 minutes. Transfer to a paper towel-lined plate to drain.

Pour off all but 2 Tbs. of the fat from the pot and return to medium heat. Add the remaining 1 Tbs. butter, the onion and celery and sauté until softened, about 7 minutes. Add the celery seed and cook, stirring often, until fragrant, about 1 minute. Add the stock, increase the heat to medium-high and bring to a boil. Add the celery root and chestnuts and return to a boil, then reduce the heat to low, cover partially, and simmer until the celery root is tender when pierced with the tip of a knife, about 25 minutes. Meanwhile, crumble the bacon and set aside.

Working in batches, transfer the soup mixture to a blender and process to a smooth puree. Pour the puree into a clean pot. Add the half-and-half, 1 1/2 tsp. salt and pepper, to taste. Set the pot over medium-low heat and cook gently, stirring occasionally, until the soup is heated through, about 10 minutes.

Taste the soup and adjust the seasonings. Ladle into warmed bowls, garnish with the bacon, croutons and the remaining 2 tsp. sage, and serve immediately. Serves 6 to 8.

Adapted from Williams-Sonoma New Flavors for Soup, by Adam Ried (Oxmoor House, 2008).