Begin by greasing a 9×13 baking dish using non-stick spray. In a bowl, combine the melted butter and finely ground digestive biscuit crumbs. Transfer the mixture to the baking dish and press it down evenly to form a firm crust. Place the dish in the refrigerator to chill.

If you opt for Cool Whip: In a mixing bowl, beat together 8 ounces of Cool Whip and the cream cheese until the mixture becomes fluffy and well combined. Add the powdered sugar and vanilla extract, continuing to beat until fully incorporated. If you prefer homemade whipped cream: Pour the heavy whipping cream into a separate bowl and beat until soft peaks form, approximately 5 minutes. Set aside around 2 cups of the whipped cream.

Combine the cream cheese, vanilla extract, and powdered sugar with the remaining whipped cream, stirring until just blended.

Retrieve the baking dish from the refrigerator. Spread the Cool Whip or whipped cream mixture evenly over the graham cracker crust. Arrange the thinly sliced bananas in a single layer on top, gently pressing them down. Next, evenly distribute the crushed pineapple over the banana slices.

Spoon the remaining Cool Whip or whipped cream on top, using a knife to ensure the bananas and pineapple are fully covered. Cover the dish with foil and refrigerate for at least 4 hours. Prior to serving, garnish with chopped walnuts, maraschino cherries, chocolate syrup, or sprinkles, according to your preference. Slice and serve. For the best experience, consume the dessert within 2-3 days.