01 -  Preheat oven to 400°F and line a baking sheet with parchment paper. 
 02 -  In a large mixing bowl, whisk together flour, sugar, baking powder, and salt until evenly blended. 
 03 -  Add cubed cold butter to dry ingredients and use a pastry blender or fingertips to work the butter in until the mixture forms coarse crumbs. 
 04 -  Stir in chopped walnuts to distribute throughout the flour mixture. 
 05 -  In a separate bowl, whisk together heavy cream, maple syrup, egg, and vanilla extract until fully combined. 
 06 -  Pour wet mixture over dry ingredients and gently stir until just incorporated; avoid overmixing. 
 07 -  Transfer dough to a lightly floured surface. Pat into a 7-inch round, about 1 inch thick. Cut into 8 equal wedges. 
 08 -  Place each wedge on the prepared baking sheet, spacing them slightly apart. Brush the tops with extra heavy cream. 
 09 -  Bake for 16 to 18 minutes, until the scones are golden brown. Transfer to a wire rack to cool slightly. 
 10 -  In a bowl, whisk together powdered sugar, cinnamon, maple syrup, and enough milk to achieve a thick but pourable consistency. 
 11 -  Drizzle cinnamon icing over warm scones and let icing set before serving.