In a large mixing bowl, whisk together the flour, cornmeal, sugar, baking powder, and salt. Add the cold butter and use your fingertips or a pastry cutter to rub it into the dry ingredients until the mixture resembles a coarse sand-like texture
Gently fold in the raspberries , being careful not to crush the berries much. Work quickly, the goal is to keep everything cold.
In a separate bowl, whisk together the egg, buttermilk, cream, and vanilla. Pour this over the flour mixture and stir with a fork or spatula just until a shaggy dough forms. Do not overmix
Turn the dough out onto a lightly floured surface, and fold and pat together until you achieve a cohesive dough (still shaggy, but a better formed mass)
Gently pat into a rough rectangle, then cut in half and stack the halves. Repeat this stacking and patting process 1–2 more times. This will build natural layers and gives the scones extra height and flakiness
Once stacked, shape the dough into a 6-inch round, about 1½ inches thick. Wrap and freeze for 1 hour (or overnight). This rest helps the butter firm back up, which will help prevent spreading in the oven
Remove the dough from the freezer and cut into 8 even wedges with a sharp knife or bench scraper. Place the wedges on a parchment-lined baking sheet and freeze for another 15–20 minutes while you preheat the oven to 400°F (200°C)
Just before baking, brush the tops with heavy cream and sprinkle with turbinado sugar. Bake for 22–30 minutes, until golden and the tops feel firm and crisp. Let cool on a wire rack for 10–15 minutes before glazing.
In a small bowl, mix the powdered sugar, raspberry powder, and cream or milk until you reach the consistency you prefer. Adjust the liquid as needed. Drizzle over the scones while they’re slightly warm or fully cooled. not too hot or your gaze will just melt off
Lastly, add a bit of crumbled freeze dried raspberries if you'd like, and you're done!