Spray a cold wok or large skillet with cooking spray. Preheat over medium heat. Add kosher salt and Szechwan peppers or whole black peppers. Stir-fry for 5 to 7 minutes or until the whole peppers begin to pop and smoke. Remove the wok from the heat. Let the mixture cool to room temperature. Grind the mixture in a food processor, clean coffee grinder, or with a mortar and pestle. Store in a tightly covered container. Makes about 1/2 cup.