Position a rack in the center of the oven and preheat the oven to 400ºF. Place a sheet of parchment paper on a baking sheet, set aside.

Place the flour, sugar, baking powder, baking soda, salt, and orange zest in the bowl of an electric mixer fitted with the paddle attachment (you can also do this in a regular bowl with an electric mixer). Stir to combine.

Add the butter and mix the ingredients on the low setting until the butter incorporates with the flour. Let the mixer run on the low setting while you drizzle in each of the following ingredients separately, vanilla extract, egg, heavy cream, and sour cream. Fold the cranberries and pistachios into the dough until combined.

Flour your work surface and your hands before removing the dough from the mixing bowl. Work the dough into a neat 10 inch circle. Cut into 8 equal pieces using a sharp knife or a dough scraper. Place the scones 1 ½ - 2 inches apart on the baking sheet. Brush with the remaining 2 tablespoons of heavy cream and sprinkle with sparkling sugar if desired.

Bake the scones for 19-22 minutes or until lightly golden and cooked through. Remove from the oven and allow to cool for several minutes. You can make the glaze while they cool. Combine the confections sugar, vanilla and 2 tablespoons of the orange juice in a bowl and mix until smooth. If the glaze is too thick, you can drizzle in the remaining tablespoon of orange juice, 1 teaspoon at a time to help thin it out (3 teaspoons = 1 tablespoon). Drizzle glaze over the scones and top with additional sparkling sugar if desired.