Preheat the oven to 450 degrees F.
Rub the salmon with olive oil and season with cumin,chili powder, salt and pepper. Place salmon, skin side down, on a non-stick baking sheet.
Bake until salmon is cooked through, about 12 to 15 minutes.
Meanwhile make the salsa, combine the avocado, mango, cilantro, lime juice and salt in a bowl and mix well, chill until ready to use.
Serve the salmon topped with the avocado-mango salsa.