Whip the Cream: In a large, chilled bowl, combine the heavy whipping cream, powdered sugar, and vanilla extract. Use an electric hand mixer to beat on medium-high until stiff peaks form.

Prep the Dish: Spread a very thin layer (about 1/4 cup) of the whipped cream across the bottom of a 9×13-inch baking dish.

First Layer: Arrange a single, flat layer of Oreo cookies over the cream. Break cookies as needed to fill any empty spaces.

Second Layer: Spread about one-third of the remaining whipped cream evenly over the cookies.

Repeat: Add another layer of cookies, followed by another layer of whipped cream. Repeat once more, finishing with a smooth layer of whipped cream on top.

Chill: Cover the dish tightly with plastic wrap. Place in the refrigerator to chill for at least 6 hours, or preferably overnight.

Serve: Just before serving, crush 3-4 leftover cookies and sprinkle them over the top for garnish. Slice and serve cold.