Roll the dough out into a long rectangle, around 27cm x 42cm (10½" x 16"), with the longer end facing you. If it struggles against you a little, cover it and leave it to rest for five minutes.
Spread the butter over the top of the dough with a brush or knife.
Mix the sugar and cinnamon together and then sprinkle over the top of the butter layer. Move it around with your fingers to get a nice, even coverage and push it down slightly.
Carefully, still with the longer edge facing you, roll the dough up fairly tightly, finishing off with the seam underneath.
Cut the roll into 12-15 slices. Then, cut each slice into 2, 3 or 4 pieces (depending on the size of the slice). It doesn't matter how big the slices or pieces are, just make them fairly uniform in size so that they bake evenly.