Tips: Pepitas (hulled pumpkin seeds) can be found in the bulk-foods section of natural-foods stores or Mexican groceries.
Place a salmon fillet on a clean cutting board, skin side down. Starting at the tail end, slip the blade of a long, sharp knife between the fish flesh and the skin, holding the skin down firmly with your other hand. Gently push the blade along at a 30° angle, separating the fillet from the skin without cutting through either.
Place pepitas in a small dry skillet and cook over medium-low heat, stirring constantly, until fragrant and lightly browned, 2 to 4 minutes.