Preheat oven to 350-degrees. Line a 13x9-inch pan with parchment paper and lightly apply butter or nonstick spray along the bottom and sides.
In a large bowl, mix the flour, brown sugar, and salt. Add the cold butter and use a pastry blender or a fork to mash it down into small crumbles. The overall mix will feel sandy, but it'll hold together after baking.
Pour the crust mixture into the prepared pan. Use some wax paper and a heavy glass to compress the crumbs.
Bake for 15 minutes or until edges are lightly browned. Set aside as you make the filling.
Lightly beat the eggs in a large bowl. Add the maple syrup, melted-and-cooled butter, brown sugar, white sugar, and salt, stirring until combined. Stir in the pecans to coat.
Pour filling over the partially baked crust. Bake for another 30 to 35 minutes, or until filling is set.
Cool bars to room temperature and then use the overhanging parchment to lift the contents out to cut into bars. Store in a sealed container for up to a week, or freeze bars for later enjoyment.
OM NOM NOM!