Turn the dough out on to the counter. It shouldn't be sticky and be easy the handle. Do not use flour when rolling out the dough or it will make the pinwheels tough).
Gently roll the dough out into a rectangle. 60cm x 30cm is a good size to aim for. It doesn't have to be perfect, but the bigger you an get it, to more perfect swirls you will get.
Brush the butter over the rectangle of dough, leaving a 10cm gap on one of the long edges. You need to leave a gap so that dough will stick to itself when you roll it.
Now sprinkle over the mozarella, parmesan and diced ham so that it covers the area of dough spread with the butter.
Once the filling is spread, roll the dough into a log, starting on the opposite long edge to the gap you've left.
Roll the dough into a tight log, using the unfilled dough to seal the log. You can spray a little water on the part where the dough joins if you want to - but the dough should stick to itself without it.Lay the log out with the seam underneath. Cut the log into approximately 12 pieces (you can measure and divide by 12 if you want them to look even - or just go freehand if you're not too fussed). Using dental floss to cut them will help you keep their shape and give the pinwheels a flat surface.
Place the pinwheels onto a baking sheet lined with parchment paper. You can also make these in a cast iron skillet if you prefer, but they will join together.