Line a 9×9-inch dish with plastic wrap and freeze for 15 minutes to prepare the base
In a bowl, mix crushed graham cracker crumbs with 1/2 cup Biscoff until clumps form when pressed
Press the mixture firmly into the frozen dish to create a compact base
Brush caramel sauce over banana slices to ensure even coating
Lay the caramelized banana slices over the base in an even layer
In a bowl, combine 3 cups cold milk, 1/3 cup Biscoff spread, and dissolved gelatin until smooth
Pour the slightly runny pudding mixture over the banana layer while still fluid
Top with a dollop of whipped cream or mini caramel candies
Place plastic wrap directly on the pudding surface and freeze for 4 hours
Let the pudding thaw for 15 minutes at room temperature before slicing into portions