Fire up your grill for indirect cooking.
Tear off a large piece of foil, about 2' long.
Combine all of the ingredients minus 1/3 cup of the French-fried onions in a large bowl.
Pour the bowl contents out onto the center of the foil and fold up the edges to seal it.
Place on your grill over indirect heat and cook 25-30 minutes, rotating the packet once, until the potatoes are tender.
Serve garnished with the remaining French-fried onions.