Banana Cream Pie

1 9-inch baked pastry shell
3 tbs cornstarch
1 2/3 cups water
1 14-oz can sweetened condensed milk
3 egg yolks, beaten
2 tbs margarine or butter
1 tsp vanilla extract
3 medium bananas
lemon juice from concentrate
whipped cream

In a heavy saucepan, dissolve cornstarch in water; stir i sweetened condensed milk and egg yolks. Cook and stir until thickened and bubbly. Remove from heat; add margarine and vanilla. Cool slightly. Slice 2 bananas; dip in lemon juice and drain. Arrange on bottom of prepared crust. Pour filling over bananas; cover. Chill 4 hours or until set. Spread top with whipped cream. Slice remaining banana. Dip in lemon juice, drain and garnish top of pie.
Refrigerate leftovers.