Preheat oven to 425 degrees and place rack in center of oven.
Place flour, sugar, baking powder, baking soda, and salt into a large bowl.
Add butter to bowl and cut butter into dry ingredients using a pastry cutter.
Add buttermilk all at once, and stir gently with a fork just until wet and dry ingredients are incorporated. Fold the dough together a few times in bowl.
Place the dough onto a floured surface such as a clean counter or a cutting board and pat gently into approximately a 9x15 rectangle.
Make the filling ingredients by combining gently in a bowl. Spread over dough.
Roll up as with cinnamon roll dough, starting from long side.
Using a sharp knife, cut dough into 10 even pieces. Try to not crush the dough while cutting!
Place dough into a lightly greased 9x13 pan.
Bake at for 15 to 18 minutes or until golden. Let cool for 10 minutes, then drizzle with icing.
Make icing by whisking ingredients together until smooth. Drizzle over warm biscuits.