1. Preheat oven to 375°. Stir together first 3 ingredients, and spread onto bottom of a 9-inch pie plate. Fit 1 piecrust over pecan mixture in pie plate, allowing excess crust to hang over sides.
2. Stir together Granny Smith apples and next 5 ingredients. Spoon mixture into crust, packing tightly and mounding in center. Place remaining piecrust over filling; press both crusts together, fold edges under, and crimp. Place pie on an aluminum foil-lined jelly-roll pan. Cut 4 to 5 slits in top of pie for steam to escape.
3. Bake at 375° on lower oven rack 1 hour to 1 hour and 5 minutes or until juices are thick and bubbly, crust is golden brown, and apples are tender when pierced with a long wooden pick through slits in crust. Shield pie with aluminum foil after 50 minutes, if necessary, to prevent excessive browning. Cool on wire rack 10 minutes. Place a serving plate over top of pie; invert pie onto serving plate. Remove pie plate, and replace any remaining pecans in pie plate on top of pie. Let cool completely (about 1 hour).