Preheat oven to 425 degrees. Prepare pastry for two-crust pie; place one crust in bottom of pie plate, reserve second crust for top. Stir together apple slices and brown sugar; pour into pastry-lined pie pan. Top with butter and 3TBS of syrup. Cover with top crust; cut slits in top; seal and flute.
Bake at 425 degrees 15 minutes; remove from oven. Make crisscross cuts about 1-inch apart through top of crust and filling. Drizzle remaining 3TBS syrup on top. Cover edge with 2-3-inch strip of aluminum foil to prevent excessive browning. Bake 25 minutes longer.