- 2 pounds unpeeled or peeled deveined shrimp, preferably wild American
- 1 small onion, sliced
- 1 lemon, thinly sliced
- 8 bay leaves
- 2 tablespoons fresh oregano leaves
- 2 tablespoons Worcestershire sauce
- 1 tablespoon Old Bay seasoning
- 2 teaspoons hot chili paste (such as sambal oelek)
- 2 teaspoons kosher salt
- 1/4 teaspoon freshly ground black pepper
- 1/2 cup (1 stick) unsalted butter, cut into tablespoons
- Ingredient info: Hot chili paste is sold at Asian markets and many supermarkets.
- Using small kitchen scissors, cut shrimp shells along the curved backs. Remove vein, keeping shell intact. (Skip this step if using peeled deveined shrimp.) Toss shrimp and next 9 ingredients in a large bowl.
- Place four 16×12″ sheets of heavy-duty foil on a work surface. Divide shrimp mixture among sheets. Fold all foil edges toward the center to accommodate the liquid; do not crimp. Add 2 tablespoons butter and 1/4 cup water to each. Crimp tightly to seal. Preheat oven to 325°F. Arrange packets in a single layer on a rimmed baking sheet. Alternatively, build a medium fire in a charcoal grill, or preheat a gas grill to medium-high. Bake or grill until shrimp are just opaque in center (carefully open 1 packet to check; steam will escape), about 30 minutes. Carefully cut open packets.