Place cold butter between two pieces of parchment paper. Using a rolling pin, pound it out as thinly as possible without it breaking (about 1/4").
On a lightly floured surface, roll out the dough to a 1/8" thickness.
Place butter on top of the dough making sure that the rolled out dough is big enough to envelope the butter completely when folded over.
Sprinkle all the sugar on top of the butter. Try to make the layer of sugar as even as possible.
Fold the dough over the butter and sugar and seal the edges so that no butter or sugar is peaking out.
Using the rolling pin and working very quickly, pound the dough envelope until it's very thin, but be careful that the sugar doesn't tear through the dough.
Fold the dough into thirds like a piece of paper so that you have a rectangle.
With the seam side down, pound the dough again until it's thin, but stop before the sugar seeps out.
Repeat the last two steps.
When you have a big square, fold in the corners to make a smaller square. Repeat this step to make it an even smaller square.
Place the dough square in a 9" cake pan lined with parchment paper, cover in plastic wrap and proof for 1 hour.
Preheat oven to 375F.
Bake cake until the top is golden brown, approximately 40 minutes.