1-First Step: Prepare the Pan Line an 8×8-inch square baking pan with parchment paper, letting some hang over the sides so you can lift the slab out later. Coat the parchment and the exposed pan edges with cooking spray. This helps prevent sticking and makes slicing much easier later.

2-Second Step: Make the Cookie Crust Place the vanilla wafer cookies and granulated sugar in a food processor and pulse until the mixture becomes fine crumbs. If you do not have a food processor, crush the cookies in a sealed bag with a rolling pin until they are very fine. Transfer the crumbs to a bowl and stir in the melted unsalted butter until the mixture looks evenly moistened. The crumbs should hold together when pressed. Pour the crust mixture into the lined pan and press it firmly into an even layer. Use the bottom of a measuring cup or glass to help pack it down. Freeze the crust for 15 minutes so it sets before you add the filling.

3-Third Step: Mix the Vanilla Cream Layer In a medium bowl, whisk the 2 boxes of vanilla instant pudding mix with 2.5 cups cold heavy cream. Whisk until the mixture is smooth and thickened. You want a creamy texture with no dry pockets of pudding mix. Spread the pudding mixture over the chilled crust in an even layer. Smooth the top with a spatula so the chocolate layer can sit neatly on top. Refrigerate the pan for at least 10 minutes to help the custard firm up.

4-Fourth Step: Make the Chocolate Ganache Place the chopped semi-sweet chocolate or chocolate chips in a heatproof bowl. In a small saucepan, heat the 2/3 cup cold heavy cream just until it reaches a simmer. Do not let it boil hard. Pour the hot cream over the chocolate and let it sit for about 1 minute, then whisk until glossy and smooth. Let the ganache cool slightly before pouring it over the custard layer. If you want a smoother finish, let it cool for about 3 minutes. If you want a softer, swooping top, let it rest for about 5 minutes. Spread the chocolate gently so you do not disturb the layer underneath.

5-Final Step: Chill, Slice, and Serve Refrigerate the bars for at least 2 hours so the layers set fully. Once chilled, lift the slab out of the pan using the parchment overhang. Cut into 12 or 16 pieces, wiping the knife between cuts for neat edges. Serve the bars cold for the best texture and cleanest layers.