Preheat oven to 175°C.
In a bowl mix together flour, sugar, salt, baking powder and baking soda.
Grate chilled butter directly into the flour.
Rub the butter into the flour with your finger tips.
Add cranberries, sour cream and milk and bring the dough together.
Do not knead it. Just press it to form a crumbly dough.
Take small portions of the dough, flatten it and arrange on a baking tray.
Bake in the preheated oven for 30 - 35 minutes or until the top is golden.
Serve warm with butter and jam.