Fit piecrust into a 9-inch pieplate according to package directions; fold edges under, and crimp.
Beat eggs and next 5 ingredients at medium speed with an electric mixer until smooth. Stir in chopped pecans; pour into prepared piecrust. Arrange pecan halves on top.
Bake at 350° for 50 minutes, shielding edges with aluminum foil after 30 minutes to prevent excessive browning.