Banoffee Tart

To make filling: Preheat oven to 425 degrees. Bring a pot of water to a boil. Pour condensed milk into a 9-inch deep-dish glass pie plate. Cover with foil. Place pie plate in a large roasting pan and place pan on center oven rack. Pour boiling water into roasting pan halfway up sides of pie plate. Bake 2 hours, whisking milk 2 times, until thickened and caramel colored. Remove pie plate to wire rack. Whisk milk until smooth, and let cool. To make tart shell: Lower oven temperature to 300 degrees. In the bowl of a heavy-duty mixer with paddle attached, mix flour, sugar, and salt on low speed until blended. Add butter and blend until mixture is the texture of fine meal. With mixer running, drizzle in egg yolks and mix until dough begins to come together. Gather dough into a ball and flatten into a disc. Wrap and freeze until firm, about 40 minutes. Cut dough into 4 pieces. Using the large holes of a box grater, grate dough into an 11-inch tart pan with removable bottom. Press dough firmly and evenly against sides and bottom of pan. Prick bottom with a fork. Freeze 15 minutes. Line tart shell with foil and fill with dried beans or rice. Bake tart shell in lower third of oven 30 minutes. Remove foil and beans. Return to oven and bake until golden brown, 25 to 30 minutes. If shell puffs up during baking, press it down with the back of a spoon. Remove to rack to cool. Peel and thinly slice bananas. Arrange half of bananas in concentric circles, slightly overlapping, to cover bottom of tart shell. Spoon on caramelized milk and spread to cover bananas. Arrange remaining bananas over milk. Cover tart with plastic wrap, pressing wrap against bananas, and refrigerate 1 hour. To make topping: In the bowl of a heavy-duty mixer with whisk attachment, combine cream and sugar. Using a paring knife, scrape seeds from vanilla bean into cream. Beat mixture until just stiff. Spread over bananas and sprinkle with grated chocolate.