Once the dough has risen, make the filling. In a medium bowl, add the softened butter, brown sugar, cinnamon and salt. Use a silicone spatula to mix together until it makes a paste. Set aside.
Lightly grease a 9x13 baking pan with butter, set aside.
On a lightly floured surface, roll the dough out in a 20x12ish inch rectangle, it doesnt have to be perfect. Spread the cinnamon butter mixture all over the dough.
Use a pizza cutter to cut eight, 2.5 inch strips. Roll each strip away from you, then carefully transfer them to a lightly greased 9x13 baking pan.
Cover the pan with a clean kitchen towel. Allow the rolls to rise in a relatively warm environment for 60 minutes or until double in size.
Once the rolls have doubled in size, preheat the oven to 350°F (190°C). Pour the heavy cream all over the cinnamon rolls.
Bake for 30 minutes, or until lightly browned. If you notice the tops are getting too brown too quickly, loosely tent the pan with aluminum foil and continue baking. If you want to be precise about their doneness, their internal temperature taken with an instant read thermometer should be around 195–200°F when done. Remove pan from the oven and place pan on a wire rack as you make the icing.