Make the salsa - Cut the veggies in half, place in a food processor, pulse until you have small uniform pieces like a pico. Chill until serving.
In a shallow dish, mix the salt, paprika, garlic and onion powders, cayenne, black pepper, oregano, and thyme. Generously coat fish fillets with spice mixture. Heat a large cast-iron skillet over medium-high heat, and add olive oil. Add fish and cook until browned on each side and until flesh is white opaque (cooked through) and spices are toasted. Transfer to plates, and serve.
COOKS NOTE: When blackening, make sure to use a heavy skillet (like cast iron) that can take the necessary high heat.