A chainsaw seems to be the popular method up in this neck of the woods. With that being said I’ve got an antique Ice Saw hanging in the cabin just begging to get back in the game.
If there’s nuthin in the kitchen drawer to shave or crush it with, sometimes will just leave in bag and whack it on the counter till the plastic starts breaking. Timing can be a critical issue here. Be sure not to shake the container too much.