I make these Grilled Garlic Parmesan Potatoes on a propane grill because a propane grill is so much easier for me. You just turn it on, wait for it to come up to temperature, and it's ready to go. When you're done cooking, you can just turn it off. You definitely can make these on a charcoal grill instead, if that's all you have. It's just not as easy to turn that on and off. Since charcoal grills generally don't have a temperature gauge on them like a gas grill does, your temperature may vary. So that may change your cook time as well.