In a mixing bowl, whisk together cold milk, sweetened condensed milk, and instant vanilla pudding mix until smooth. Chill for at least 15 minutes.

In another bowl, beat the heavy whipping cream until stiff peaks form, then set aside.

Gently fold the whipped cream into the chilled pudding mixture until combined.

In a 9x13-inch dish, layer half of the pudding mixture.

Slice the ripe bananas and layer them over the pudding.

Crumble Biscoff cookies over the banana layer.

Spread the remaining pudding mixture over the cookies and top with another layer of banana slices and crumbled cookies.

Cover and refrigerate for at least 2 hours before serving.