I'd be tempted to try a cookie cutter, a piece of wood and a woodworking G clamp, and leave it clamped overnight to see if it cuts through.
I have no idea if it would work, though.
If it does work you could make them in the shape of gingerbread men !
I have no idea if it would work, though.
If it does work you could make them in the shape of gingerbread men !