Begin by finely crushing the Oreo cookies until you have a texture resembling sand. Reserve ½ cup of the crumbs for later topping. Press the remaining crumbs firmly into a 9x13 inch baking dish to form a solid base.

In a large mixing bowl, beat together the softened cream cheese, unsalted butter, and powdered sugar using a hand mixer on medium speed until smooth and fluffy, about 2-3 minutes.

Gently fold the thawed whipped topping into the cream cheese mixture using a spatula, aiming for a light and airy quality.

In a separate bowl, whisk together the instant vanilla pudding mix and cold milk until thickened, approximately 5 minutes.

Fold the thickened pudding into the cream cheese and whipped topping mixture until fully combined and smooth.

Spread the creamy filling evenly over the prepared crust, then sprinkle the reserved Oreo crumbs, mini Oreos, and pastel chocolates on top.

Cover with plastic wrap and refrigerate for at least 2 hours to allow it to set properly.