01 - Whisk cold milk and instant vanilla pudding mix in large bowl for 2 minutes. Let stand 5 minutes until thickened.
02 - Stir sweetened condensed milk into pudding until fully incorporated and smooth.
03 - Whip 1 cup heavy cream to soft peaks in separate bowl. Gently fold whipped cream and vanilla extract into pudding mixture.
04 - Arrange single layer of Biscoff cookies in bottom of trifle dish or 9x13-inch baking dish.
05 - Top cookies with half of banana slices, then spread half of pudding mixture over bananas.
06 - Repeat layers with remaining cookies, bananas, and pudding mixture, ending with pudding on top.
07 - Cover and refrigerate at least 4 hours or overnight to meld flavors and soften cookies.
08 - Whip remaining 1 cup heavy cream with powdered sugar and 1/2 teaspoon vanilla extract until stiff peaks form.
09 - Spread whipped topping over chilled pudding. Garnish with crushed Biscoff cookies and banana slices if desired. Serve cold.