Infusing pork butt with pink peppercorns and garlic enhances its superb flavor. The vermouth in the pan sauce has a masterful synchronicity with the juniper-like aroma of pink peppercorns and gives you enormous complexity from just one ingredient.
Let pork stand at room temperature 1 hour. Preheat oven to 350°F with rack in middle.
04Roast pork, fat side up, until an instant-read thermometer inserted into center of meat registers 150°F, 1 1/2 to 2 hours. Transfer pork to a cutting board and let rest 30 minutes.
05Meanwhile, pour off all but about 1 tablespoon fat from roasting pan. Add vermouth to pan and boil, scraping up brown bits, 2 minutes. Stir in broth, any meat juices from cutting board, and remaining 2 tablespoons pink peppercorns and boil until reduced to about 1 1/2 cups, about 5 minutes.
06Knead together butter and flour, then whisk into sauce and boil, whisking constantly, until just slightly thickened, about 2 minutes.