Preheat oven to 218 C. Sift flour, baking powder, sugar and salt into a large mixing bowl.
Transfer to a food processor. Cut butter into cubes and add to flour, then pulse 6 or 7 times until the mixture resembles rough crumbs. (Alternatively, cut butter into flour in the mixing bowl using a grater, fork or a pastry cutter.)Or i mix by hand manually.
Return dough to bowl, add buttermilk and stir with a fork until it forms a rough ball (don’t worry if it is a little sticky).
Turn the dough out onto a floured surface and pat it into a rough rectangle, about an inch thick.
Fold it over and gently pat it down again. Repeat 5 times.
Gently roll out the dough some more, so that it forms a rectangle.
Cut dough into biscuits using a floured glass or biscuit cutter.
Do not twist cutter when cutting; this will crimps the edges of the biscuit causing it not to rise.
If you have scraps just reform a rectangle and cut additional biscuits.
Place biscuits on a baking sheet and bake until golden brown, approximately 10 to 15 minutes. Serves 6 to 8.