Combine the blackening spices together in a small bowl until mixed well.
Brush the shrimp generously with melted butter.
Generously coat each with blackening seasoning.
If using a cast iron skillet, pre-heat to medium-high and cook shrimp for 1-2 minutes per side.
If using a BBQ grill, thread shrimp onto skewers and grill over medium-high heat, 1-2 minutes per side. The shrimp should be pink and opaque. Serve hot.