Place salmon fillets on a baking sheet and season with salt and black pepper.
Combine pecans, maple syrup, vinegar, paprika, chipotle powder, and onion powder in a food processor; pulse until the texture is crumbly. Spoon pecan mixture on top of each salmon fillet, coating the entire top surface. Refrigerate coated salmon, uncovered, for 2 to 3 hours.
Preheat the oven to 425 degrees F (220 degrees C).
Bake salmon in the preheated oven until fish flakes easily with a fork, 12 to 14 minutes.