Prepare the Crust: Preheat your oven to 350°F (175°C). In a medium bowl, combine the graham cracker crumbs, melted butter, and granulated sugar. Mix until well combined. Press the mixture firmly into the bottom of a greased 9×9-inch baking dish to form an even layer. Bake for 8-10 minutes, then remove from the oven and let it cool.
Make the Filling: In a large mixing bowl, whisk together the milk and instant banana pudding mix until it thickens (about 2 minutes). Add the vanilla extract and gently fold in the whipped cream until combined.
Assemble the Bars: Pour the banana pudding filling over the cooled crust, spreading it evenly. Place the sliced bananas on top of the pudding layer.
Add the Topping: Spread the remaining whipped cream over the banana layer. If desired, sprinkle crushed graham crackers on top for added texture.
Chill: Cover the dish with plastic wrap and refrigerate for at least 2-3 hours, or until set.
Serve: Once set, cut into bars and serve chilled. Enjoy your delicious banana pudding bars!