Vacuum Pressed Butter Slab for Laminated Dough

I was looking for an easy way to make a slab of butter for laminated dough, and this worked a dream. I used the two sizes of vac bag in the first pic to plan out how big I wanted to roll the dough out. Then I vac sealed the butter (straight out of the fridge, no need to soften), flattened initially by hand, then used the rolling pin to fill all the corners of the bag with butter.
To remove, put the bag in the freezer for 30-45 mins until it is frozen hard. Cut open and peel away the bag. It is soft enough to work after 10-15 minutes sitting on the dough.