Lightly grease a 10-inch cast iron skillet. On a lightly floured surface, roll thawed dough into a 12” x 10” rectangle. In a small bowl, mix together sugars and cinnamon. Brush dough with 2 tablespoons melted butter. Evenly top butter with sugar mixture and optional nuts. Beginning with the 12-inch side (long side), tightly roll the dough, stopping in the center. Repeat this step on the opposite side to meet in the middle. Cut the dough into 8 equal slices. Pinch the bottom of each slice to make the heart shape. Place the 7 slices in prepared pan with the points facing in towards the middle. Place the last slice in the center of the ring. Brush the dough with one tablespoon of remaining melted butter. In a warm area, let rise until double in size. Bake in a preheated 375° oven for 15-20 minutes or until light golden brown. Remove from oven and brush again with remaining melted butter. When cool, drizzle with icing.