This is an easy one, and is a big hit with everyone I've fed it to.
Get new potatoes or red potatoes, and cut them into bite sized peices.
Put the potatoes on heavy aluminum foil, large enough to make as flat a pouch as you can. If you are making lots of potatoes, make serveral pouches. They cook better when the potatoes are flatter in the pouch.
Coat the peices with olive oil.
Mix in slices of butter.
(optional, you can also add sliced onions and/or garlic)
Shake GrillMates Montreal Steak Seasoning very generously over the potatoes.
Seal the pouch(es).
Cook on medium heat (400) for 20-40 minutes.
Key here is to check it after 20 minutes and make sure your potatoes are crisping, but not burning. If you poen to check them, stir them and leave the pouch open. Also be careful not to puncture the bottom of the pouches, as the olive oil will ignite and charr your spuds.