Prepare a small baking sheet by covering it in parchment paper. Be sure you also have freezer space for it to rest flat.

Chop the butter into 1"cubes and leave it in a bowl in the refrigerator.

Combine the baking powder, baking soda, salt, sugar, and flour in the bowl of a large food processor. Pulse several times to mix completely.

Add the butter in a few cubes at a time with the processor on low until the butter is pea-sized.

Pour the butter-flour mixture out into a large bowl and add the buttermilk. Mix until just combined.

Turn dough out onto floured surface and flatten into a 1" thick square with your hands. 

Cut the square into four equal pieces and stack them, placing any loose flour or dough pieces in between the layers. Flatten out again into a 1" square. 

Cut into equally sized squares (9-12 squares, depending on how large you like your biscuits).

Place the cut biscuits onto the prepared baking sheet and chill in the freezer for ten minutes.

Biscuits can be placed in a bag and frozen for up to 6 months.

While the biscuits are chilling, preheat the oven to 425F.

Cut small slivers of butter (two per biscuit). Remove the baking sheet from the freezer and place one sliver of butter under each biscuit and one on top of each biscuit. 

Bake biscuits for 20-25 minutes, or until golden brown on top.