I'm sure I have nothing on any French bakers out there, but I think this is slick. I got 300 grams of butter into a 10" x 10" tile with barely any effort by using a ziploc. It chills in the fridge into a nice wafer. When ready, I'll trim the sides, peel off the plastic and voila, fold, fold, fold - croissants!
The Stonehenge of chilled butter
Use of this in croissants