Preparing the Pie

• In a saucepan, whisk together the sugar and cornstarch. 
• Whisk in the milk and place over medium heat.
• Bring the mixture to a boil, whisking frequently.
• In a separate bowl, add the egg yolks.
• Pour about ½ cup of the milk mixture into the egg yolks slowly, whisking constantly.
• Pour the egg mixture back into the saucepan, still stirring constantly and cook until bubbling.
• Remove from the heat and stir in the vanilla and butter.
• Pour into a bowl, cover with plastic wrap, and refrigerate until cool.
• Slice the bananas and arrange half of them on the crust.
• Pour half of the cooled pudding into the pie crust.
• Arrange the remaining bananas over the pudding and top with the rest of the pudding.
• Refrigerate until ready to serve.
• Spread the whipped topping over the pudding and garnish with sliced bananas, if desired.