Preheat your grill to medium-high heat. Place the hot dogs on the grill and cook, turning occasionally, until heated through and nicely charred, about 5-7 minutes.
Toast the hot dog buns on the grill for about 1 minute, or until lightly golden.
Place a grilled hot dog in each bun. Top with shredded cheddar cheese, chopped onion, and a spoonful of pickle relish. Add mustard and ketchup to taste.
Enjoy your classic grilled hot dogs with a side of chips or a simple salad for a complete meal.