Preheat oven to 475C. Measure self-rising flour into a large mixing bowl. Cut cold butter into small pieces (I usually cut it into ~12 pieces per stick) and add to flour. Use your fingers (or a pastry blender) to work the butter into the flour. The goal is to mix the flour and the butter while keeping some pieces of butter just big enough to help make flaky layers in the biscuits. When you are finished, the mixture should look like lumpy wet sand with no pieces bigger than a pea. Add the cold buttermilk and stir with a spoon approximately 8 times. Do not over mix. At this point, the dough should be mostly combined, but some loose flour and wetter parts of the dough will likely remain. They will be mixed in during the kneading. Dump the mixture onto a lightly floured surface. Use your hands to gently push together the dough into a ball, then flatten gently into a disk. Fold the dough in half, then repeat the flattening and folding motion approximately 5 times. The goal is for the flour mixture and buttermilk to be combined. It is essential to not overwork the dough, or the biscuits’ texture will be ruined. Flatten the dough with your hands to approximately ¾ inch thickness. Cut out rounds with a drinking glass or a biscuit cutter, if you have one. Place rounds on an ungreased baking sheet. Gently knead the remaining dough scraps back together, then flatten to ¾ inch thickness. Cut out biscuits from the remaining dough and place on a baking sheet. Bake biscuits for 11-15 minutes depending on the size (smaller biscuits will bake faster). They should be golden brown on top when they are finished.