Adjust oven rack to middle position and heat oven to 350 degrees. Line baking sheet with wax paper and spread chopped pecans in a single layer on baking sheet. Toast pecans for 3-4 minutes. Remove from oven and set aside.
Set oven to 375 degrees.
Combine cream and maple syrup. Set aside.
Mix flour and baking powder. Scatter butter over top and mix with a pastry cutter until mixture resembles coarse cornmeal.
Add toasted pecans and stir to combine.
Stir in cream and syrup mixture until dough begins to form, about 30 seconds.
Turn dough onto lightly floured counter and knead until rough, slightly sticky ball forms, about 15 seconds. Shape dough into 5-inch round, about ¾ inch thick. Cut dough into 4 wedges.
Place wedges on the same baking sheet you used for the pecans. Bake until scone tops are light golden brown. 18-22 minutes, rotating sheet halfway through baking. Transfer to wire rack and let cool for 20 minutes.
While scones bake, whisk powdered sugar and maple syrup together in bowl. Once scones are cool, drizzle with glaze. Let glaze set for 5 to 10 minutes before serving.