Prepare an 8-inch springform pan by lining with parchment paper and spraying with nonstick cooking spray.

In a bowl, combine shortbread crumbs and melted butter. Press into the bottom and halfway up the sides of the prepared pan to form the crust.

In a saucepan over low heat, melt butter and brown sugar, stirring until sugar dissolves. Add sweetened condensed milk and simmer for 16-18 minutes, stirring constantly until thick and golden.

Remove the caramel from heat and let cool slightly. Slice bananas and layer half on the crust. Pour caramel over bananas, then layer remaining bananas on top.

Whip heavy cream with confectioners' sugar until stiff peaks form. Spread evenly over the pie.

Refrigerate the pie for at least one hour before serving.