Preheat oven to at 180°C/350°F. Preheat the oven to 350°F. Process the graham crackers to form crumbs, add the melted butter and mix until the mixture resembles wet sand.
Press the crumb mixture into the bottom and up the sides of a 9-inch baking dish using the bottom of a measuring cup, a glass, or your hands. Bake for 5-7 minutes and let it cool.
Cover the cooled crust with dulce de leche. Arrange the banana slices over the dulce de leche and cover with whipped cream. Top with chocolate shavings if using. Chill in the refrigerator for at least 30 minutes before serving.
