1) Preheat oven to 350 degrees F. Line a baking sheet with parchment paper.

2) In a medium bowl, whisk together flour, brown sugar, cinnamon, baking powder, salt, and cream of tartar.

3) Cube butter and cut it into the dry ingredients using a pastry cutter or your clean fingers. The butter should be in pea-sized pieces when done.

4) In a small bowl, whisk together egg and sour cream. Stir wet stuff into the dry ingredients until it just comes together in a loose ball. If the mixture is very dry, add more sour cream by the tablespoon until it comes together. Try not to overwork the dough.

5) Press the dough out on a lightly floured surface into a 1/2 inch thick round. Cut scones out using a medium cookie cutter. You should get 8 scones out of the batch.

6) Press each scone in the cinnamon sugar mixture on both sides and place on the baking sheet. Dust scones with pinches of cinnamon sugar.

7) Bake scones at 350 degrees F. for 18-20 minutes until flakey and browned around the edges. Let cool briefly before serving.