* Preheat oven to 400 degrees F. Line a baking sheet with parchment paper and set aside.
* In a large bowl whisk together the flour, sugar, baking powder and salt.
Grate the frozen butter using a grater or food processor and place it into the bowl.
Working quickly, combine the flour and butter using a pastry blender or fork. work it until it is crumbly.
Stick the flour mixture in the fridge or freezer while you combine the wet ingredients.
In a small bowl combine the sour cream, heavy cream, egg, vanilla extract and orange zest. Pour it over the flour mixture and gently stir to combine, just until everything is moistened.
Fold in the cranberries. Flour your hands and work the dough together. Lay it onto a floured surface. Using a rolling pin, gently roll to one inch thickness.
Form it into one large square.
Cut the dough into squares them in half to make triangles. Place the scones on your baking sheet and brush the tops of them with a little bit of heavy cream.
Bake for 12 -15 minutes, until the bottoms are golden
Remove scones from the hot baking sheet and allow them to cool for at least 10 minutes before drizzling the glaze on top.