Chopped pecans,optional For the crust: Chop pecans very fine,preferably in a food processor fitted with a metal blade.Place in bowl with other crust ingredients and mix until well blended.Divide in half and press into the bottom of 2 pie pans.Chill 30 minutes. Bake the pie crusts for 25 minutes @ 350 degrees.Cool completely. For chocolate layer:Melt chocolate with butter and corn syrup in the top of a double boiler set over hot,not boiling water.Stir frequently. Remove from heat and cool,then stir in vanilla.Divide between cooked pie crusts and spread evenly. For Filling:Heat milk in a medium size saucepan over medium heat to scald.Beat the egg yolks and gradually add sugar.Then beat in flour. Gradually stir in hot milk.Transfer to medium saucepan and cook,stirring constantly over medium high heat(use a whisk).The mixture will lump as it begins to thicken.Bring the mixture to a boil and boil 1 minute,stirring constantly.Remove from the pan from heat and continue to stir until the mixture is smooth.Then,beat in butter and optional rum.Cool to room temperature. Peel the bananas,slice very thin and toss with lemon juice.Whip 1 cup of the cream until it is firm but not stiff.Mix about quarter of the cream into the cooled egg mixture to lighten it,then fold the remaining cream and bananas into egg mixture.Fill the pastry shells with banana cream and smooth to even.Beat remaining cream until stiff. Spoon around edge of the pies and sprinkle with chopped pecans,if desired.Makes 2 pies.