Pat the peeled and deveined shrimp very dry with paper towels. If you prefer to rinse them first with lemon water or diluted vinegar, rinse quickly, pat them thoroughly dry, and sanitize the sink and surrounding surfaces afterward.
Place the shrimp in a bowl and season with the black pepper, onion powder, garlic powder, smoked paprika, Old Bay and Debbie’s Caribbean Soul Spice. Because the jerk marinade and Old Bay may already contain salt, start with only ¼ to ½ teaspoon salt, then adjust the finished sauce if needed.
Heat the olive oil and 2 tablespoons of the butter in a large skillet over medium-high heat.
Arrange the shrimp in a single layer. Sear for approximately 1½–2 minutes on each side, just until they begin turning pink and opaque. Do not cook them completely. Transfer the shrimp to a plate.