To answer the original question....it would have to be the standard Montana summer barbecue. You go to someone's house, they hand you a can of Busch Light, you drink a couple of those, then the host turns on his gas grill.
He goes into the house, and comes out with a white cardboard box, that is filled with frozen hamburger patties. Skinny little things. They haven't quite thawed yet. The host places on them on the grill, and since they are a little bit frozen (you don't want to risk eating raw meat), he burns the snot out of them.
Then you get a bun out of the bag (toasted? never!), put on some delmonte catsup, French's mustard, Miracle whip, maybe some sliced supermarket tomato, yellow onion, iceberg lettuce, Nalley's sweet pickle relish...and you got yourself a Montana-style burger.
To be washed down with another Busch Light.