Preheat the BBQ to a medium heat (350°F).

Place the halved potatoes and chopped onion on a big sheet of foil. Drizzle on the oil and season to taste with salt and pepper.

Fold up the sides of the aluminum foil sheet and crimp the edges to make a tightly sealed packet. Make sure there is some extra space in the aluminum foil package to let air circulate.

Put the package on the top grill of your BBQ and cook for 25-30 minutes or until tender.

Note: Heat may vary from one BBQ to another. Periodically check to make sure you are not overcooking your potatoes.