1 ½ cups diced yellow onion or a combination of diced onions and shallots (1 cup onion, ½ cup shallots)
Coarse salt and freshly ground black pepper to taste
1 ½ pounds mixed fresh mushrooms, any tough stems discarded and roughly chopped
1 teaspoon fresh thyme leaves (use half if dry)
¼ cup Madeira, Marsala, or sherry, or ½ cup white wine
Crackers or matzo
Sieved hard-boiled egg
Chopped flat-leaf parsley and/or chives
Small pickles or cornichons
Additional caramelized onions or pickled shallots or red onion
Combine dried mushrooms and boiling water in a small bowl and let soak for 30 minutes. Remove mushrooms, finely chop and set aside. Strain soaking liquid through a paper towel or coffee filter to remove any grit and set it aside.
Heat olive oil and 2 tablespoons butter over medium-high heat. Add onions and shallots, if using, and cook for 7-8 minutes, until they brown at the edges. Raise heat to high and add fresh mushrooms, thyme, salt and pepper. Cook, sautéing, until mushrooms brown further and release their liquid. Cook until all of the liquid has evaporated, then add Madeira, Marsala, sherry, or wine and do the same. Add rehydrated mushrooms and their soaking liquid, and cook this almost completely off. No liquid should run into the center if you drag your spoon through the mushrooms, clearing a path. Adjust seasonings to taste—seasoning is everything here—and then stir in last tablespoon of butter.
Let mixture cool to lukewarm, then blend in a food processor or blender until desired consistency (pate is traditionally very smooth). Let chill in the fridge for a few hours before serving, giving the flavors a chance to settle. Keep the pate in the fridge for up to 5 days, in an airtight container.
Serve with crackers and the garnishes of your choice.
Peel a fully cooled hard-boiled egg, cut into quarters, and press each quarter, yolk-side down through a fine-mesh sieve. This creates decorative egg flakes that you can use as a beautiful garnish for your pate.
Pickled Red Onions or Shallots
Combine ¼ cup red wine vinegar, ¼ cup cold water, 1 tablespoon Kosher salt, and 1 tablespoon granulated sugar in a jar.
Add thinly sliced onion or shallot and cover with lid; let pickle in the fridge (ideally for at least an hour. Pickled onions will keep for 2 weeks in the fridge.
While the original recipe includes porcini and cepe mushrooms, you may use any mushrooms you like. Cremini mushrooms, chanterelle, and oyster are good choices, but you may use any that you like the flavor of. You may also skip the alcohol if you would like, the mushroom stock gives it plenty of flavor when used alone.