- Pasta:
- 14 ounces all-purpose flour
- 3 1/2 ounces chestnut flour
- 1 pinch salt
- 3 tablespoons extra-virgin olive oil
- 4 eggs
- 4 egg yolks
- Sauce:
- 2 tablespoons butter
- 2 large leeks – washed, trimmed, and thinly sliced
- 2 tablespoons minced shallot
- 2 cloves garlic, chopped
- 1 tablespoon olive oil
- 2 pounds mixed varieties of fresh mushrooms
- 1 cup dry white wine
- 1 bunch fresh parsley, minced
- 2 tablespoons shredded Parmigiano-Reggiano cheese, or to taste
- Whisk flour, chestnut flour, and salt in a bowl; stir in 3 tablespoons olive oil, eggs, and egg yolks to make a smooth dough. Form dough into a ball, wrap in a cloth towel, and let rest for 1 hour.
- Roll pasta into thin 5×12-inch sheets on a floured work surface; cut sheets into 1×12-inch ribbons. Let pappardelle pasta dry on a kitchen towel sprinkled with flour while you complete remaining steps.
- Melt butter in a large skillet over medium heat; cook and stir leeks, shallot, and garlic until white part of leeks becomes translucent, about 5 minutes. Heat 1 tablespoon olive oil in a separate skillet over medium heat; cook and stir mushrooms in hot olive oil until the liquid evaporates and mushrooms turn golden brown, 10 to 15 minutes. Mix mushrooms into leek mixture.
- Stir white wine into mushroom-leek mixture and scrape up and dissolve any browned bits of food on the bottom of the skillet. Bring to a boil, reduce heat to low, and simmer mushroom-leek mixture until mushrooms are tender, about 5 minutes.
- Bring a large pot of lightly salted water to a boil; cook the pappardelle pasta at a boil until tender and pasta floats to the top of the water, about 5 minutes; drain. Transfer pasta to a serving bowl, toss lightly with mushroom-leek mixture and parsley, and top with Parmigiano-Reggiano cheese.