mushroom soup with hazelnut gremolata

Every fall, I look at the wild mushrooms in the market and think, “wow these are expensive.” So I asked myself how to get lots of flavor out of them without spending lots of money. The answer is this soup, which I created for an article in October’s Bon Appetit. It starts with a base of inexpensive button mushrooms (or small brown creminis) then a few exotic ones are sauteed to go on top. I finish it with a crunchy hazelnut gremolata for great texture contrast. It’s woodsy and bosky and great for a holiday dinner.
Photo credit: Stephen Lewis for Bon Appetit
ingredients
1/2 ounce-package dried porcini
4 tablespoons butter
1 small onion, chopped
1 large carrot, chopped
1 pound regular or cremini mushrooms, sliced
kosher salt
3 cups vegetable broth
12 ounces wild mushrooms, such as chanterelle, fresh porcini, or shiitake
hazelnut gremolata
1/2 cup chopped parsley
1 clove garlic, chopped
1 organic orange
1/4 cup finely chopped peeled hazelnuts (see note)
kosher salt
1/3 cup olive oil
directions
Put dried porcini in a bowl and pour 1 cup steaming hot water over them. Set aside to soak.
Melt 2 tablespoons of the butter in a soup pot and add onion and carrot; cook over medium-high heat until softened, about 5 minutes. Add the 1 pound sliced mushrooms and a good pinch of salt. Cover the pot and cook for about 5 minutes until the mushrooms soften and give off some liquid, then add the broth and bring to a boil. Strain the soaked porcinis through a coffee filter into a measuring cup, then add the strained liquid to the soup pot. Roughly chop the porcinis and add them to the pot. Reduce heat and simmer soup, covered, until flavors blend, about 20 minutes.
While soup is cooking, wipe any dirt from the gills or caps of the wild mushrooms with a damp paper towel; trim off dry ends of stems (if using shiitakes, discard stems). Slice or chop wild mushrooms and set aside.
Make gremolata: put parsley and garlic on a board, then grate the zest of the orange right over them. With a knife, mince all together. Transfer to a small bowl with the nuts and olive oil; add salt to taste and more olive oil if necessary to make the mixture moist enough to drizzle. Set aside. In a wide frying pan, melt the remaining 2 tablespoons butter and add the chopped wild mushrooms and a pinch of salt; saute until slightly browned at edges. Remove from heat and set aside (do not add to soup pot).
When soup base is ready, puree in the pot with an immersion blender or transfer in batches to a regular blender and puree (let cool first if using a regular blender). Wipe out pot, then pour pureed soup back in it. Reheat if necessary. Divide soup among shallow bowls and top evenly with sauteed wild mushrooms and hazelnut gremolata.
note: you can buy chopped, peeled hazelnuts, but doing it yourself gives better flavor. Toast the nuts on a baking sheet in a 350° oven until skins start to crack and nuts smell fragrant (about 10 minutes). Put nuts in a fine-mesh sieve in the sink and with a clean towel, rub nuts against sieve to slough off skins (not all the skins will come off). Chop nuts by hand or pulse in a processor.