01 - Preheat the oven to 400°F and line a baking sheet with parchment paper.
02 - In a large bowl, whisk together flour, sugar, baking powder, salt, and orange zest until well combined.
03 - Add the cold butter cubes and cut into the dry mixture using a pastry cutter or fingertips until the mixture resembles coarse crumbs.
04 - In a small bowl, whisk together the heavy cream, egg, and vanilla extract until smooth.
05 - Pour the wet mixture over the flour mixture and stir gently until just combined. Fold in cranberries and nuts if using. Do not overmix.
06 - Turn the dough onto a lightly floured surface and pat into a 1-inch thick circle. Cut into 8 wedges and transfer to the prepared baking sheet, spacing apart.
07 - Brush the tops with a little extra heavy cream. Bake for 18–20 minutes until golden brown. Cool on a wire rack.
08 - Whisk together powdered sugar, orange juice, and orange zest until smooth. Drizzle over cooled scones.