1/2 cup cornstarch
1 cup sugar
4 cups milk
8 egg yolks
1 tablespoon unsalted butter
1 tablespoon vanilla extract
5 to 6 firm, but ripe bananas, cut in 1/4-inch thick slices
Whipped cream, for garnish
Preheat oven to 375 degrees F.
Combine melted butter and crumbs. Press into glass pie pan so crust is approximately 1/4-inch thick and forms a lip at the rim.
Bake for approximately 10 to 12 minutes, until golden and set. Set aside to cool.
Meanwhile, in a large bowl, combine cornstarch and 1/2 cup of sugar. Add 1 cup milk and egg yolks, and whisk to combine well.
Combine remaining 3 cups milk with remaining 1/2 cup of sugar in a pan and bring just to a boil. In a slow stream, pour hot milk mixture into egg mixture in bowl, whisking constantly. Return mixture to stovetop and cook, whisking constantly, until very thick and bubbly.
Whisk in butter and vanilla extract, strain mixture, and set aside to cool slightly.
To assemble, spread a 1/4-inch layer of lukewarm pastry cream on bottom of cooked and cooled crust. Top with a layer of banana slices in concentric circles (as close together as possible) to completely cover. Top with another layer of pastry cream, then bananas, until you have three layers of bananas. The top layer should be pastry cream. Chill then serve garnished with whipped cream.