How to Make It
Preheat oven to 400°.
Whisk together the flour, potato flakes, sugar, baking powder, and salt in a large mixing bowl. Cut the butter into the flour mixture using a pastry cutter or your fingertips until coarse and crumbly. Transfer bowl to freezer; freeze 5-10 minutes. Fold the berries into the dough.
Form a small well in the center of flour and butter mixture; pour in heavy cream. Stir until just mixture just comes together; do not overwork the dough. Turn the dough out onto a lightly floured surface. Gently press the dough into a 7- to 8-inch round; cut the round into 8 wedges using a sharp knife. Place the scones 2 inches apart on a parchment paper-lined baking sheet.
Brush the tops of the scones with remaining 2 tablespoons of heavy cream and sprinkle with turbinado sugar, if desired. Bake at 400° for 15 to 20 minutes or until golden. Cool slightly before glazing.
To prepare the citrus glaze, whisk citrus juice into the sifted confectioners’ sugar until desired consistency is reached. Whisk in the vanilla, salt, and zest. Drizzle glaze over cooled scones.
This dough is crumbly, and that's OK! Press the dough together (you can even give it one or two gentle kneads) so that it is cohesive, but avoid overworking the dough. Overworked dough makes for a tough scone.