In a large mixing bowl, pour in the heavy whipping cream and beat it using an electric mixer on medium speed until soft peaks form, about 3-5 minutes.

Gently add the mascarpone cheese, powdered sugar, and vanilla extract to the whipped cream. Continue mixing on medium speed until well combined and stiff peaks form, roughly 2-3 minutes.

Take a 9x13 baking dish and lay out the ladyfingers in a single layer, trimming them if necessary.

Brush half of the orange juice over the arranged ladyfingers. Allow them to soak for a minute.

Spread half of the mascarpone mixture over the soaked ladyfingers using a spatula.

Arrange half of the sliced bananas over the mascarpone mixture, keeping them evenly distributed.

Repeat the layering process with the remaining ladyfingers, orange juice, mascarpone mixture, and banana slices.

Spread the cool whip over the top layer of banana slices, sealing in the layers.

Cover the dish with plastic wrap and refrigerate for at least 4 hours, overnight is ideal.

Garnish with additional banana slices before serving, then slice into portions and enjoy.