Preheat the oven to 400 degrees. Line a baking sheet with parchment paper and set aside.
Combine the flour, sugar, baking soda, baking powder and salt in a bowl, and whisk well. Cut the butter into the flour mixture until the mixture is like coarse meal and the butter is in small, pellet-sized pieces (slightly smaller than a pea). I like to use my hands, but you can also use a pastry cutter, or your food processor, just don't over process. You still want visible chunks of butter.
Pour in the buttermilk and toss with a fork. The dough should start to come together but you don’t want to overmix the dough. If there are lots of dry patches throughout the dough, add a bit more buttermilk, just a tablespoon or two at a time until the dough comes together (it’s ok to have dry bits here and there). Use a bench scraper to gather up the loose bits and press them into the mass of dough Fold the dough over onto itself to help it come together and to create some layers. Work it just enough until it is a rough mass that mostly holds together with some flour spots here and there. The less you work the dough, the more tender your biscuits. Do not knead the dough or handle roughly.
With a lightly floured rolling pin (or pressing quickly with your hands), roll the dough into a 1/4-inch rectangle, about 18X10 or thereabouts. Roll quickly – the more the dough is worked with and processed, the less flaky and tender the rolls will be.
Spread the melted butter over the top. Combine the sugar and cinnamon and spread evenly over the butter.
Roll the cinnamon rolls, beginning with one long edge, rolling tightly without pulling and stretching the dough. Reposition the long roll until it is seam side down.
Use a serrated knife or a bench knife/scraper to cut into 1- or 1 1/2-inch rolls. Tuck the loose end of each roll underneath and place an inch or so apart on the prepared baking sheet(s).
Bake 12-15 minutes until they start to brown and then cool 10 minutes. Whisk together icing ingredients and spread the icing on top.