Spread the butter evenly over the dough, going all the way to the edges.
In a small bowl, combine the brown sugar, flour, zest, cardamom, and salt.
Sprinkle the brown sugar mixture over the butter.
Starting with the longer side, roll the dough into a log and then pinch to seal the seam. Roll the log over so that the seam side is down.
Using a sharp knife, cut in half lengthwise, stopping about 1 inch from the end.
Starting near the top that is not cut, gently lift one of the cut halves over top of the other cut halve. (a twist) Continue to twist 2-3 more times.
Hold one end and then start twisting the dough around it, creating a circle of dough. Try to get the cut, exposed layers of the dough, facing upwards.
Place the dough ring in an 8-inch or 9-inch prepared skillet (I used butter) and let rise for one hour, covered.