Step 1: In a large bowl, whisk together the sweetened condensed milk and ice-cold water until thoroughly combined, preparing the base for your Magnolia Bakery banana pudding recipe.
Step 2: Add the instant vanilla pudding mix and whisk for about 2 minutes until no lumps remain. Cover and refrigerate for at least 4 hours or overnight until completely set.
Step 3: Once the pudding mixture has set, in a separate large chilled bowl, whip the heavy cream using a hand mixer or stand mixer until stiff peaks form.
Step 4: Gently fold the set pudding mixture into the whipped cream until no blue or yellow streaks remain and the mixture is a uniform, light pale yellow.
Step 5: To assemble the Magnolia Bakery banana pudding recipe, select a large glass bowl or trifle dish. Spread a small amount of pudding on the bottom.
Step 6: Place a layer of Nilla wafers over the pudding, followed by a layer of sliced bananas. Top with one-third of the remaining pudding mixture.
Step 7: Repeat the layers (cookies, bananas, pudding) two more times, finishing with a smooth layer of pudding on top. You can crush some extra cookies for a garnish.
Step 8: Cover tightly with plastic wrap and refrigerate for at least 4 hours (up to 8 hours) to allow the cookies to soften perfectly before serving your Magnolia Bakery banana pudding recipe.