Preheat a large skillet over medium heat.
In a small bowl, mix together paprika, chili powder, garlic powder, salt, black pepper, oregano, onion powder, and cayenne pepper until combined. Stir in avocado oil or olive oil.
Brush both sides of each cod filet with the oil mixture.
Add cod filets to the skillet and cook for 3-4 minutes on each side, until cod is cooked through. Cod should reach an internal temperature of 145F and the flesh should be opaque and easily flaked with a fork.
While the cod is cooking, prepare the avocado corn salsa. Add corn, avocado, tomato, red onion, cilantro, lime juice and salt in a bowl. Stir to combine. Taste and add lime and/or salt as needed.
Top the blackened cod filets with the avocado corn salsa and serve.