Preheat your oven to 400°F (200°C). Line a large baking sheet with parchment paper.
In a large bowl, whisk together 4 cups of flour, 1/4 cup of granulated sugar, the baking powder, salt, and orange zest.
Add the cold, cubed butter. Use a pastry blender or your fingers to cut the butter into the flour until it forms coarse crumbs with some pea-sized pieces of butter still visible.
In a separate bowl, whisk together the 4 beaten eggs and the cold heavy cream.
Pour the wet ingredients into the dry ingredients. Stir with a spatula until just combined into a shaggy dough. Gently fold in the dried cranberries.
Transfer the dough to a well-floured surface. Gently knead 2-3 times to bring it together. Pat the dough out to a 3/4-inch thickness. Use a floured 3-inch round cutter to cut out scones. Place them about 2 inches apart on the prepared baking sheet. Gently re-pat scraps to cut more scones.
In a small bowl, whisk together the egg and milk for the egg wash. Brush the tops of the scones with the wash and sprinkle with the remaining 1 tablespoon of granulated sugar.
Bake for 20 to 25 minutes, or until golden brown and firm to the touch. Let the scones cool on the pan for 10 minutes before transferring to a wire rack.
While the scones cool, whisk together the confectioners' sugar and orange juice to make the glaze. Drizzle the glaze over the warm scones before serving.