Add flour, sugar, baking powder, 1 tablespoon orange zest, and salt to a large mixing bowl. Stir with a fork until combined.
Grate the frozen butter on a box grated straight into the bowl with the flour mixture. Using your hands and working quickly, pinch the butter into the flour until the mixture comes together into pea-sized crumbs. Place the bowl in the freezer for 5-10 minutes.
In a smaller bowl, whisk together ¾ cup heavy cream, egg, and vanilla extract.
Remove the bowl from the freezer and add the frozen cranberries. Pour over the cream mixture and mix everything together until combined.
Transfer dough onto a floured work-surface. Using floured hands, form into a ball. Press the dough into a disk and slice it into 6 large wedges. Brush the scones with the remaining heavy cream.
Line a baking sheet with a piece of parchment paper and arrange the scones. Place in the refrigerator for 10 to 15 minutes to firm dough.
Meanwhile, preheat oven to 400°F while the scones firm in the refrigerator. Bake 20-25 minutes until golden brown. Let cool for a few minutes while you make the glaze.
For glaze, whisk powdered sugar and 1-1/2 tablespoons orange juice in a small bowl until smooth. Drizzle glaze over the scones and serve immediately. Enjoy!