Adjust an oven rack to the middle position, and preheat the oven to 400F. Line a sheet pan with parchment paper.
Combine the flour, oats, baking powder, sugar, and salt in a bowl of a food processor. Process until combined. Add the butter, and pulse until butter is pea-sized. Move the flour mixture to a large bowl.
Whisk together the buttermilk, maple syrup, and eggs. Pour the liquid ingredients over the flour mixture, and mix just until combined, making sure there are no dry pockets. Turn mixture out onto the prepared pan, form into an 8-inch circle that is 1 inch thick. Cut the circle into 8 even pieces, and brush the tops with a little bit of buttermilk.
Bake for 20-25 minutes, until the bottom of scones are golden brown. Let scones cool 5 minutes before applying glaze.
To make the glaze: Combine the confectioners’ sugar, maple syrup, and vanilla. Use a butter knife or off set spatula to apply the glaze to the tops of the scones. Sprinkle with uncooked oats for garnish, if desired.