In a large bowl, combine the flour, baking powder, baking soda and salt. Cut the butter into the flour mixture with a pastry cutter or a knife and fork until only small pieces are visible. Make a well in the center of the mixture.
Add the milk or yogurt, and stir gently until the dough holds together. If you are adding any fruit, raisins, berries or other additions, stir them in with the milk. Gently shape the dough into 2 inch rounds approximately 1 inch thick and transfer to the baking sheet. Bake in a preheated over for 15 minutes, or until golden brown.