Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or lightly grease it.
In a mixing bowl, whisk together the flour, granulated sugar, baking powder, and salt until well combined.
Add the cold, cubed butter to the flour mixture. Using a pastry cutter or fork, cut the butter into the dry ingredients until the mixture resembles coarse crumbs.
Fold in the cranberries gently.
In another bowl, whisk together the heavy cream, vanilla extract, and egg until combined.
Pour the wet ingredients into the flour mixture. Stir gently until just combined, being careful not to overmix.
Transfer the dough to a floured surface and gently knead a few times until the dough holds together. Pat the dough into a circle about 1-inch thick.
Use a sharp knife or dough cutter to cut the circle into 8 equal wedges.
Place the scones on the prepared baking sheet. Beat another egg and brush it over the tops of the scones. If desired, sprinkle a little sugar on top.
Bake in the preheated oven for 18-20 minutes, or until the scones are golden brown.
Allow them to cool slightly before serving. Enjoy your cranberry scones warm or at room temperature!