Bacon, Potatoes, Onion, Garlic salt, other seasonings to taste.
Double-layer the bacon on bottom sheet of foil, staying aout 1.5″ away from edges (for folding up to seal the package), put sliced potatos on top of bacon, add garlic salt & or personal preference seasonings. Slice onions and put on top of potatos. More seasoning?
Cover with another layer of foil, and roll up the top & bottom edges of foil together to make a tight seal. Poke a single hole in top to vent. Cook on coals or on grill top (preferred) until bacon is done.