1-Line a sheet tray with parchment paper: Line a sheet tray with parchment paper and set aside.
2-Make the scones: Make the scones: In a large bowl, whisk together the all-purpose flour, light brown sugar, baking soda, cream of tartar, and salt. Then, use a pastry cutter or a fork to cut in the cold butter until the butter is about lentil-sized. In a separate bowl, whisk together the egg, ¾ cup heavy cream, and vanilla extract. Add the liquids to the flour and butter mixture and mix until just combined.
3-Transfer the dough to the parchment paper-lined: Transfer the dough to the parchment paper-lined sheet tray and pat into a circle. If the dough is sticky, sprinkle a bit of flour on the dough. Continue patting the dough until it is about an 8-inch disk. Then, use a bench scraper or knife to cut the circle into 8 wedges. Pull the wedges out a bit to leave space in between each scone.
4-Freeze the scones for at least 30: Freeze the scones for at least 30 minutes (this allows the gluten to relax and helps them firm up before baking). While the scones are freezing, preheat the oven to 400°F.
5-In a small bowl, mix together the: In a small bowl, mix together the turbinado sugar and ground cinnamon. Remove the scones from the freezer, then brush the tops with a little bit of heavy cream. Sprinkle the tops with the cinnamon-sugar mixture.
6-Bake the scones in the preheated oven: Bake the scones in the preheated oven for 25-28 minutes, or until they’re golden brown and a toothpick inserted in the middle of one comes out clean.
7-Make the cinnamon glaze: Make the cinnamon glaze: While the scones are baking, whisk together the powdered sugar, ground cinnamon, and milk to make the cinnamon glaze. Feel free to leave the glaze in the fridge until the scones have come out of the oven.
8-Glaze the scones and serve: Glaze the scones and serve: After the scones have finished baking, let them cool for 5-10 minutes, then drizzle the glaze over top and serve.
9-Stored tightly in an airtight container, these: Stored tightly in an airtight container, these scones will stay fresh at room temperature for up to 2-3 days or up to 2 months in the freezer.