1. Preheat oven to 400° F. Stack two large baking sheets on top of each other and line the top one with parchment paper. This will create an insulated surface for the scones to bake on and prevent the scones from browning too much on the bottom.
2. In a large bowl, whisk the flour, baking powder, sugar, and salt. In a 2-cup liquid measuring cup, whisk the buttermilk, vanilla, egg, and lemon zest together until well-combined.
3. Drop the cold butter pieces into the flour and toss lightly to coat with flour. Cut in the butter with a pastry blender, two knives, or your fingers. The butter should be about the size of small peas.
4. Stir the freeze-dried fruit into mixture, lightly breaking up the larger berries, if desired.
5. Stir the liquid ingredients into the dry ingredients just until a craggy dough comes together. Dump the dough out onto a clean work surface and fold any loose flour into the dough with your hands.
6. Pat the dough into a 12-inch square. Fold the dough into thirds like a business letter from left to right (a dough scraper really helps with these steps). Fold the short ends of the dough into the center in thirds, to form an approximate 4-inch square. Press the dough back into a 12-inch square and repeat from top to bottom. Repeat once more from right to left. Pat the dough into a 12×4-inch rectangle and cut into 4 squares then cut each square in half diagonally into 8 equal-size triangles. Transfer the scones to the baking sheet and chill for 15 minutes or freeze for 5. Brush each scone with heavy cream and sprinkle with coarse sugar.
7. Bake for 19-24 minutes, until the tops are golden brown. Transfer the baking sheet to a wire rack to cool for 5 minutes then transfer the scones to the rack to cool for a few more minutes. Serve warm or at room temperature.

Storage: Scones are best on day 1 so I recommend only baking what you plan to eat. You can freeze the cut dough before baking for up to 2 months. Add a couple extra minutes to the bake time when baking from frozen.