Place 2 large pieces (at least 20 inches long) of heavy-duty aluminium foil over each other to form a cross.
Place potatoes and onion in middle of foil. Sprinkle with cheese, butter, garlic, parsley, salt and pepper; drizzle with olive oil. Carefully toss with clean hands to coat potatoes.
Fold up the sides of the foil to form a 'bowl' and pour chicken broth over potatoes, then fold foil down and seal pouch well.
On grill/fire: Over medium heat, cook potatoes in foil for 30-40 minutes, or until tender.
In oven: Bake foil packet at 425°F for around 30-35 minutes, or until done.
Careful when opening the packets – hot steam will escape!
