Divide the dough into four equal parts. Wrap the three dough balls that still have to wait in cling film to prevent them from drying out and set them aside in a cooler place, not the fridge but also not that close to the oven.
You will only need to butter the tin before you bake the first layer of crust.
Roll the first dough ball into a rough rectangle on a lightly floured surface, place it on the buttered baking tin, and roll again until the dough layer is as large as the baking tin: 32x22 cm/12x9 inches approximately (or similar size, it doesn't have to be so exact). And don't stress too much about having perfectly straight edges, you will cut those away before slicing and serving the cake.
Bake for about 10 minutes or until slightly golden around the edges. Take out of the oven and while holding one side of the tin with a gloved hand, run the blade of a long knife underneath the crust. Let it slide carefully and slowly onto a cooling rack.
Repeat with the remaining dough balls.
Keep in mind that the tin is now very hot, don't touch it when rolling the dough on top, and use gloves when you transfer it to the oven.
When the crust layers are baked, you can carefully staple them one on top of the other, they will not stick. Let them cool completely.