A handful of dried porcini mushrooms (1 ounce)
4 cups beef stock
2 1/2 to 3 pounds cubed beef chuck, at room temperature
Kosher salt and coarsely ground pepper
1/4 cup EVOO, plus more for drizzling
2 tablespoons butter
4 large or 5 or 6 medium portobello mushroom caps, gills scraped, cut into 1-inch cubes
2 tablespoons fresh thyme leaves, chopped
1 onion, chopped
4 cloves garlic, smashed
1/2 cup dry red wine
2 tablespoons Worcestershire sauce
4 ribs celery with leafy tops, thinly sliced on an angle
1 cup fresh flat-leaf parsley tops, coarsely chopped
Juice of 1/2 lemon
1/2 cup shaved pecorino cheese
In a small saucepan, combine the porcini and 2 cups of the stock. Bring to a boil over medium heat. Reduce to a simmer and cook until the mushrooms are very tender and the liquid is reduced by one-third or so, 10 to 15 minutes. Reserving the soaking liquid, scoop out the mushrooms and chop.
Meanwhile, in a Dutch oven, heat 2 tablespoons EVOO (2 turns of the pan) over medium-high heat. Pat the meat dry and season with salt and pepper. Working in two batches, brown the meat until evenly crusted all over. Transfer the meat to a plate. Repeat, using more EVOO for the second batch.
Melt the butter into the meat drippings. Add the mushrooms and thyme, and cook until well browned, 10 to 12 minutes. Season with salt and pepper. Add the onion and garlic and cook 5 minutes more. Deglaze the pan with the wine. Add the chopped porcinis, then carefully pour in the soaking liquid, leaving the last few spoonfuls in the pan as grit may have settled there. Add the remaining 2 cups stock and the Worcestershire. Return the beef and any juices to the pan. Cover and cook until the beef is tender, about 2 hours.
Make-ahead: Cool and refrigerate.
Night of: Return the beef to room temp before reheating, partially covered, over medium heat or in a 325°F oven.
In a bowl, combine the celery, parsley, lemon juice, a healthy drizzle of EVOO, pecorino cheese, and salt and pepper. Toss everything lightly together.
Serve the stew garnished with celery salad.