DIRECTIONS

1. In mixing bowl, stir together flour, baking soda, baking powder, sugar, and salt until well combined. Using a pastry cutter or your hands, cut cold butter into flour until only a few pea-sized pieces remain. In a separate bowl, stir together buttermilk and sweet potato until combined. Add to dry ingredients and use a spoon to mix ingredients together until a shaggy dough forms. Flour your hands and press the dough together until all dry ingredients incorporated into one large dough.
2. Line a 9-inch round cake pan with parchment paper and grease with cooking spray. Transfer dough to a well-floured surface. Press the dough down and use a rolling pin to roll the dough out to a 3/4-inch-thick disc. Using a 3-inch round cutter, cut out 1 biscuit from the dough and place it in the center of the prepared cake pan. Cut out 4 more biscuit rounds from the dough and place them around the perimeter of the cake pan, allowing them to touch each other and the center biscuit. Reroll the dough scraps to 3/4-inch thickness and cut out remaining 2 biscuits. Fit snuggly in the cake pan so all biscuits are touching. Transfer to refrigerator for at least 1 hour.
3. Preheat oven to 400 degrees. Brush the surface of each biscuit evenly with milk. Bake 40-45 minutes, until tops are golden brown, and the biscuits are baked all the way through.