Roast Beef with Shallot and Black Bean Sauce

Name: Roast Beef with Shallot and Black Bean Sauce
Ingredients: 2 tablespoons black peppercorns; 6 tablespoons plus 1 teaspoon Diamond Crystal kosher salt , divided; 1 ( 10-pound ) 3-rib standing rib roast; 1/2 teaspoon ground black pepper; 3/4 cup fermented black beans (from 1 [8-ounce] pkg.) (such as Double Rings); 3 tablespoons plus 1 teaspoon olive oil , divided; 16 large shallots (about 2 pounds), thinly sliced crosswise (about 6 cups); 1/2 cup (4 ounces) sherry; 1 teaspoon kosher salt; 2 tablespoons minced peeled fresh ginger (from 1 [2-inch] piece); 2 tablespoons oyster sauce; 1/4 cup unrefined peanut oil or other flavorful nut oil (such as hazelnut); 2 teaspoons vegetable oil; 12 scallions (about 6 ounces), root ends trimmed