Easy Barbecue Shrimp

24 large head-on shrimp (about 2 pounds), peeled and deveined, tails left on, shells and heads reserved
1 tablespoon cracked black peppercorns
2 teaspoons Emeril’s Creole Seasoning or other Creole seasoning
1 1⁄2 teaspoons chopped fresh rosemary
3 tablespoons olive oil
1 cup dry white wine
3 cups water
3⁄4 cup Worcestershire sauce, preferably homemade
Juice from 2 lemons (about 1⁄4 cup)
1⁄2 cup chopped onion
1 tablespoon minced garlic
1 tablespoon hot sauce
1⁄4 cup (1⁄2 stick) unsalted butter, cut into 8 pieces
Jalapeño Biscuits (recipe follows), for serving

In a medium bowl, toss the shrimp with half of the cracked pepper, 1 teaspoon of the Creole seasoning, and the rosemary until evenly coated. Cover and refrigerate until ready to use.
Heat 1 tablespoon of the oil in a 12-inch skillet over high heat. Add the shrimp shells and heads, the remaining 1⁄2 tablespoon pepper and 1 teaspoon Creole seasoning, and cook, stirring a few times, for 3 minutes. Add wine, water, Worcestershire, lemon juice, onion, garlic, and hot sauce. Bring to a boil, reduce the heat to a simmer, and let gently bubble for 45 minutes. Strain through a coarse strainer; you should have about 1 cup of barbecue base.
Heat a 14-inch skillet over high heat. Add the remaining 2 tablespoons oil, then the shrimp and cook for 2 minutes, searing on both sides. Pour in the barbecue base, reduce the heat to medium, and simmer until the shrimp are cooked through, about 1 minute. Remove from the heat; whisk in the butter, one piece at a time, not adding another until the previous piece is fully incorporated in the sauce. Transfer the shrimp to a serving platter or small individual plates. Spoon the sauce over the shrimp and serve immediately with the Jalapeño Biscuits.