Pat the salmon fillets dry
Mix blackening seasoning with paprika, garlic powder, onion powder, cayenne, thyme, oregano, salt, and black pepper
Coat the salmon evenly with the seasoning
Heat a cast-iron skillet over medium-high heat
Add a small amount of oil or melted butter to the skillet
Place the salmon skin-side down if using skin-on fillets
Cook for 3 to 4 minutes without moving it
Flip the salmon carefully
Cook for 2 to 4 more minutes until cooked through
Remove from the skillet and let rest for 2 minutes
Serve immediately with lemon wedges if desired