Preheat the oven to 450°.
In an 8X8 casserole dish, add the stick of butter and place in the oven for 8 minutes or until melted.
In a mixing bowl, add in the dry ingredients and whisk together.
Next add the buttermilk to the flour mixture and stir those ingredients together.
In a separate bowl mix the cinnamon sugar ingredients.
Once the butter is removed from the oven, add about a tsp. of the cinnamon sugar.
Carefully pour the biscuit mix into the butter, spreading evenly to the corners.
Sprinkle the remaining cinnamon sugar on top of the biscuit dough.
Bake for 25-30 minutes or until golden brown.
Prepare the icing by mixing all the icing ingredients in a separate bowl.
Once mixed, spread evenly on top of the biscuits.
Serve when ready.