Sift flour with soda, salt and baking powder. Mix in the shortening with fingertips. Add buttermilk and stir. Mix all into a soft dough. Using a spoon, drop pieces of the dough about the size of a walnut onto a greased baking sheet. Leave 5 cm between each. Bake in a preheated 200ºC . oven for 10 min., or until browned.