Vegetarian Chopped Liver

This rich mushroom-walnut pâté is especially good with pumpernickel or rye bread.

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  2 oz. (4 Tbs.) unsalted butter
  
  


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  1 large yellow onion, halved and thinly sliced into half moons
  
  


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  2 fresh thyme sprigs
  
  


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  3/4 lb. cremini (baby bella) mushrooms, cut into medium dice (4-1/2 cups)
  
  


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  1/2 lb. shiitake mushrooms, stems removed, caps cut into medium dice (2 cups)
  
  


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  Kosher salt and freshly ground black pepper
  
  


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  2 Tbs. dry sherry
  
  


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  1 cup walnuts, toasted
  
  


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  1 small clove garlic, minced
  
  


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  1/2 tsp. fresh lemon juice; more to taste
  
  


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  1/4 tsp. finely grated lemon zest
  
  


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  2 hard-cooked eggs, peeled and roughly chopped
  
  


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  Extra-virgin olive oil, for drizzling
  
  


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  Flaky sea salt, for garnish
  
  


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  Thinly sliced scallion greens or chives, for garnish
  
  

Melt the butter in a 12-inch skillet over medium heat. Add the onion and thyme and cook, stirring occasionally, until the onion is dark brown, 15 to 20 minutes—it should be darker than golden, but not black. Stir in the cremini and shiitake, 1/2 tsp. salt, and 1/2 tsp. pepper; cook, stirring occasionally, until the mushrooms are soft and golden and the liquid they release has evaporated, 8 to 10 minutes. Add the sherry and cook, scraping up the browned bits from the pan, until almost evaporated, about 1 minute. Let the mixture cool to room temperature.


Transfer half of the mushroom mixture to a food processor. Add the walnuts, garlic, lemon juice, zest, 3/4 tsp. salt, and 1/2 tsp. pepper. Process until smooth, stopping occasionally to scrape down the sides of the bowl. Add the remaining mushroom mixture and the eggs. Pulse until coarsely chopped. Season to taste with more salt, pepper, and lemon juice. Serve in a crock or bowl or mounded on a platter, drizzled with olive oil and sprinkled with flaky sea salt and scallion greens or chives.