01 -  Preheat oven to 400°F (200°C). Line a baking sheet with parchment paper. 
 02 -  In a large mixing bowl, whisk together all-purpose flour, granulated sugar, baking powder, salt, and ground cinnamon until well blended. 
 03 -  Add cold, cubed butter to the flour mixture. Cut butter in using a pastry cutter or two knives until the texture resembles coarse crumbs. 
 04 -  In a separate bowl, whisk together mashed roasted sweet potato, heavy cream, egg, and vanilla extract until smooth. 
 05 -  Pour wet ingredients into dry ingredients and gently stir until just combined, being careful not to overmix. 
 06 -  Transfer dough onto a lightly floured surface. Pat into a round approximately 1 inch thick. 
 07 -  Cut dough into 8 wedges and arrange on the prepared baking sheet. 
 08 -  Brush surface of each scone lightly with additional heavy cream. Combine cinnamon and sugar for the topping, then sprinkle mixture evenly over scones. 
 09 -  Bake for 22 to 25 minutes, or until golden brown and baked through. 
 10 -  Allow scones to cool slightly on a wire rack before serving.