Preheat the oven to 400°. Arrange salmon skin-side down on a plate.
In a small bowl, whisk together the coriander, brown sugar, and chilli powder and season with salt. Rub the mixture into the salmon.
Heat 3 tablespoons olive oil in a large non-stick ovenproof skillet over medium-high heat until nearly smoking. Sear salmon fillets skin-side up to 2 minutes.
Flip the salmon, then transfer the skillet to the oven and cook for 3 minutes more or until the salmon is just cooked through.
In making the salsa, combine the shallots and red wine vinegar in a small bowl and set aside. Season it with salt and pepper.
Using a larger bowl, stir together the corn, tomatoes, avocados, and cilantro. Add the red wine vinegar and shallots mixture, along with the remaining 3 tablespoons olive oil.
Once the salmon is already cooked, reaching a minimum internal temperature of 145 degrees, you may now plate the dish.
Serving Suggestions: Add a generous scoop of salsa to a plate. Place a piece of blackened salmon next to the salsa. Garnish with remaining cilantro and lime zest.