Mix together dry ingredients. Cut in butter and potatoes. Stir in cold water with a fork and knead in the bowl until the dough comes together. If dough is too wet, add a little more flour. If too dry, add a little more water.
Spread about 1.5 inches thick on a flour-dusted baking sheet or stone.
Bake at 450 degrees for 17 – 20 minutes, or until lightly browned.
Serve warm with butter or fruit preserves.
The bannock keeps well at room temperature in a sealed container for several days.