Preheat your oven to 350 degrees.
Place the pecans on a baking sheet and toast in the oven for about 8 minutes.
Allow the pecans to cool completely and then give them a course chop. Set aside.
With the dough blade in a food processor add the flour, powdered sugar and salt. Pulse a few times to combine.
Add the diced butter and mix just until the dough resembles a course meal.
Add in the egg, ½ cup of the toasted pecans and maple syrup. Pulse until the dough just comes together, allow a little of the dry mix to remain, ensuring you don’t over mix.
Place the dough onto a lightly floured surface and gently knead the dough until combined.
Roll the dough into a log, a couple inches high. Wrap in a piece of plastic wrap and place in the freezer for about 15 minutes.
Once the dough is slightly hardened slice into approx ½ in rounds.
Place on a lined baking sheet and bake for approx 14 minutes or until the bottoms and outermost edges are very lightly browned.
While the cookies are baking you can make the buttercream. Add the butter and powdered sugar to a bowl and whip with a hand mixer until light and fluffy.
Add in the maple syrup and mix for another minute of two.
Cool the cookies on a cooling rack. Once cooled completely, smear a thin layer of the buttercream on the cookie and top with the remaining ¼ cup of chopped toasted pecans.