Combine sugar and cornstarch;Beat egg yolks until lemon colored. Add milk and stir into sugar and cornstarch.
Cook over a midium heat, starring constantly, until tick (5-6 minutes). Remove mixture from heat; add butter, vanilla and one cup of coconut, Pour into cooled pie shell crust; press a sheet of plastic wrap directly on the surface of the filling and refrigerate until the filling is cold and firm, at least 3 hours or overnight.
Top with meringue. Whisk the egg whites until frothy, then slowly add the sugar while continuing to whisk. Once the meringue reaches stiff peaks it is now ready to top the pie. Sprinkle coconut on the meringue. Bake in the oven (set to broil) for 1 minute or just until the meringue and coconut is lightly toasted and golden brown. Enjoy!