Preheat the oven to 400°F (200°C).
In a large bowl, combine the flour, sugar, baking powder, and salt.
Cut in the cold cubed butter until the mixture resembles coarse crumbs.
Add the chopped cranberries and orange zest, stirring to distribute evenly.
In a separate bowl, whisk together the sour cream, egg, and vanilla extract.
Pour the wet ingredients into the dry ingredients and gently mix until just combined.
Turn the dough onto a floured surface and shape it into a circle about 1 inch thick.
Cut the dough circle into eight wedges and place them on a parchment-lined baking sheet.
Bake for 15 to 20 minutes, or until the scones are golden brown.