Rubbing a raw potato on a grill creates a temporary non stick surface as a result of the starch in the potato.
When rubbing the raw potato on the grill you rub the raw potato on the grill grate while it's hot.
The potato being rubbed on the hot grill grate is a hack that helps prevent your food from sticking to the grill grate, especially for lean meats like chicken breast.
It can also be helpful as an alternative to other methods or using cooking spray.
To create a non stick surface on the grill grate with a raw potato.
Cut the potato by slicing the raw potato in half.
Then heat your grill and ensure that your grill is hot before applying the potato.
Next use a fork and hold the potato and rub the cut side of the raw potato against the hot grill grates.
Then grill your food as normal and the starch from the potato will create a thin and temporary barrier on the grill grates which helps reduce sticking.
The use of a potato for a non stick surface on your grill also works great for chicken, fish and vegetables and any other foods you don't want to stick to the grill grate.