Preheat your oven to 350°F (175°C). In a medium bowl, combine graham cracker crumbs, sugar, and melted butter until well mixed. Press the mixture into the bottom and up the sides of a pie dish. Bake for about 10 minutes or until lightly golden. Let it cool completely.

In a saucepan, combine brown sugar and condensed milk over medium heat. Stir continuously until it bubbles and thickens, about 5 minutes. Pour caramel filling over the cooled crust, smoothing it with a spatula. Allow to set at room temperature for 30 minutes.

Slice the firm bananas into thin rounds and drizzle with lemon juice to prevent browning. Layer the banana slices over the caramel, covering the surface completely.

In a large bowl, beat the cream cheese until smooth. Gradually add whipping cream, brewed coffee, and confectioners' sugar. Beat until light and fluffy with stiff peaks, about 3–5 minutes.

Spread the whipped cream over the bananas, creating an even surface. Chill in the refrigerator for at least 2 hours to set properly.

Before serving, shave chocolate over the top and sprinkle chopped walnuts if desired. Slice into wedges and serve chilled.