Heat oven to 450°F. Make pie crust as directed on box for One-Crust Baked Shell using 9-inch glass pie plate. Bake 5 minutes. Reduce oven temperature to 325°F.
In small saucepan, cook butter, sugar and corn syrup over low heat, stirring constantly, until sugar dissolves. Cool slightly. Stir in chopped pecans, vanilla, salt and eggs. Pour filling into partially baked crust; sprinkle with two-thirds of chopped white chocolate. Top with pecan halves.
Bake 40 minutes. Cover crust edge with strips of foil; bake 10 to 15 minutes longer or until set. Cool on cooling rack at least 2 hours.
In small resealable freezer plastic bag, place remaining white chocolate; seal bag. Microwave on High about 1 minute or until softened. Gently squeeze bag until chocolate is smooth; cut off tiny corner of bag. Squeeze bag to drizzle chocolate over pie.