Preheat oven to 450. Sift together flour, sugar, baking soda, and salt into a mixing bowl.
Cut butter or margarine into small pieces and add to dry ingredients. Blend together until mixture is crumbly.
Bake for 12 to 15 minutes, until golden brown. Best served warm.
Make a well in the center of the mixture and gradually add the buttermilk, stirring gently with a fork. Fold in fruit and nuts. Mix just until soft dough is formed. (We use a food processor and pulse once for the dry ingredients and blend until just after all the buttermilk is added).
Turn onto a lightly floured surface pat into a circle ½ inch thick at the edge, with the center slightly thicker. Cut into 8 equal pieces. Place each of the 8 pieces on an ungreased baking sheet.