Pappardelle With Mushrooms and Cashew Cream

To make the sauce, put a single layer of the fresh mushrooms in a large, nonstick pan over medium-high heat and cook, turning as necessary until both sides are seared and well-browned (you may need to work in batches). Remove the mushrooms to a plate or bowl and set aside. Reduce the heat to medium and add the olive oil to the pan. When shimmering, add the shallots and chopped chard stems and a generous pinch of salt and cook, stirring frequently, until the shallots are soft, about 5 minutes. Add the garlic and capers and stir constantly until fragrant, about 1 minute. Add the sherry and cook until the wine is almost all evaporated, scraping up any bits of mushroom that may have stuck to the pan while searing. Add the caper brine, 1½ cups of the reserved mushroom stock, ½ cup of the reserved pasta cooking water and the miso, stirring to break up the miso. Return the seared mushrooms to the pan, add the sliced porcinis and the chard leaves, bring to a simmer, cover and cook until the chard has wilted and the flavors have melded, about 15 minutes. Add the cashew cream and stir to blend. If needed, add more mushroom broth and/or pasta water a little at a time until the sauce lightly coats the back of a spoon and is very pourable. Season to taste with salt and freshly ground black pepper. Stir in most of the parsley, reserving a few pinches for garnish.