You grind it into powder. No one has to see what it looked like before.
I thought Klingons limited their imbibing to drink? We don't get to see anything else because the only time we see smoking in Star Trek as far as I can remember is Talbot in V. If they weren't so uptight about showing smoking (yeah we know humans have evolved past it..) I bet there would be heaps of scenes where people speculated that it wasn't straight tobacco.
Was there smoking in that bar Worf went into with the round lady singer singing Klingon opera?