Combine the butter, graham crumbs, and brown sugar in a large bowl. Press the mixture into a 9-inch pie dish, forming a shell, and bake until firm, about 10 to 12 minutes. Remove the pie dish from the oven and allow it to cool slightly.
In a large bowl combine the eggs, corn syrup, maple syrup, sugar, flour, and vanilla. Mix until well incorporated. Add the pecans and mix until all the ingredients are evenly distributed. Pour the mixture into the graham cracker crust. Bake until the filling sets, about 40 to 45 minutes. Remove the pie from the oven and cool completely before cutting. Slice into portions and serve with a scoop of vanilla ice cream.