Combine all ingredients in a food processor and process until well combined. Set aside.
For the salmon:
Place a cast iron or heavy bottomed skillet over medium-high heat. Melt ½ teaspoon of the coconut oil in the skillet. Place 1 salmon filet in the skillet, skin side down. Season the flesh with salt and pepper. Cook 2-3 minutes until skin starts to turn golden brown and crisp up. Flip and cook an additional 1-2 minutes so that the flesh side gets crispy but the center is still medium rare. Time will vary depending on thickness of the salmon filet. Repeat with remaining 3 filets, using ½ teaspoon of coconut oil to sear each time.
Prepare the salsa by adding the tomatoes, corn, red onion, feta, cucumbers and avocado to a bowl. Season with salt and pepper to taste. Pour ¾ of the basil vinaigrette into the bowl and toss until well combined.
Serve the salmon filets with the salsa and drizzle with remaining basil vinaigrette.