Place your salmon fillets on a plate, skin-side down. Pat them dry with a paper towel.
In a small bowl, combine the paprika, brown sugar, kosher salt, onion powder, garlic powder, cayenne pepper, dried oregano and dried thyme. This is your blackening magic!
Melt the butter in a separate bowl. Brush it over the top of each salmon fillet, then distribute your spice blend on top. You can press a bit the spices into the salmon to make sure they adhere well.
Heat a large cast iron skillet over medium heat. No oil is needed here, the butter on the salmon is more than enough. When the pan is hot (test with a drop of water and it should sizzle), add the salmon fillets flesh-side down. Cook for 2-3 minutes until you achieve that gorgeous blackened crust.
Gently turn the salmon over to crisp up the skin side, cooking for another 5-6 minutes. The goal is an internal temperature of 145°F, so if you have an instant-read thermometer, now's the time to use it. If not, look for the salmon to flake easily with a fork.
Once cooked to perfection, squeeze a wedge of lemon over each fillet and serve with a sprinkle of fresh parsley or thyme. Add a couple of lemon wedges on the side.