In a large mixing bowl, toss shrimp with garlic powder, onion powder, Italian seasoning, red pepper flakes (if using), salt, and black pepper until evenly coated. Set aside.
2 lbs raw shrimp, 1 tbsp garlic powder, 1 tbsp onion powder, 1 tbsp Italian seasoning, 1/2 tbsp red pepper flakes, 1/2 tsp salt, 1 tsp black pepper