01 - Whisk together olive oil, lemon juice, Cajun seasoning, smoked paprika, garlic powder, onion powder, thyme, oregano, salt, black pepper, and cayenne pepper in a large bowl until fully combined.
02 - Add the shrimp to the bowl and toss thoroughly to coat evenly with the spice mixture. Cover and refrigerate for 20 minutes to allow flavors to penetrate.
03 - Heat a grill or grill pan to medium-high temperature. If using wooden skewers, soak them in water for 20 minutes beforehand to prevent charring.
04 - Thread the marinated shrimp onto skewers if desired for easier handling and turning during cooking.
05 - Place shrimp on the preheated grill and cook for 2 to 3 minutes per side until opaque throughout and lightly charred with nice grill marks.
06 - Transfer the grilled shrimp to a serving platter, sprinkle generously with fresh parsley, and accompany with lemon wedges for squeezing over the top.