Freeze the flour and butter for at least 1 hour.
Preheat oven to 475F. Most modern ovens have a bell that goes off once the oven has reached the temperature. Wait until the bell goes off to ensure the oven is preheated properly. Line a cookie sheet with parchment paper and spray with non stick spray.
Before we start the recipe, keep the buttermilk in the refrigerator until ready to add to the recipe. I suggest keeping it in the back of the refrigerator, which is the coldest part of the fridge.
In a large bowl, combine flour, baking soda, baking powder and salt. Mix to combine.
Grate the butter. Add it to the flour. Using a pastry blender, cut the butter into the flour until it resembles coarse crumbs.
Add buttermilk, reserving 1 tablespoons for the tops and mix until just combined.
Turn the dough onto a lightly floured surface. Sprinkle a little flour on top.
Gently roll the dough into a square about 3/4” high.
Using a biscuit/cookie cutter dipped in flour and cut biscuits out.
Place on prepared cookie sheet, with biscuits touching each other.
Brush tops with remaining 1 tablespoon of buttermilk.
Bake for 15 minutes, until tops are golden.