1-First Step: Make the cookie base. Start by processing the chocolate sandwich cookies until they become fine crumbs. If you want a firmer base, mix in the optional melted butter. Stir until the crumbs look evenly moistened. This step helps the crushed cookie layer hold together when you build the trifle. Press or spoon the cookie mixture into the bottom of a trifle bowl or individual dessert cups. You do not need to make it perfectly even, but a level base helps the layers look neat. If you like a firmer bite, chill the cookie layer for a few minutes while you move on to the pudding.

2-Second Step: Cook the chocolate pudding layer. In a saucepan, heat the milk, heavy cream, vanilla, and salt over low to medium heat until the mixture starts to simmer. Keep the heat gentle so the custard does not overcook. In a separate bowl, whisk the eggs, egg yolks, and sugar until smooth and blended. Slowly pour some of the hot milk mixture into the eggs while whisking constantly. This tempers the eggs and keeps them from scrambling. Once the eggs are warmed, pour the mixture back into the saucepan and cook over low heat, stirring constantly, until it thickens into custard. Set a fine mesh sieve over a clean bowl and strain the custard if you want an extra-smooth result. Then divide the hot custard over the chopped milk chocolate and dark chocolate. Let it sit for a minute or two, then stir until the chocolate melts completely into a silky pudding. If small bits of chocolate remain, microwave the mixture briefly and stir again.

3-Third Step: Whip the cream layer. In a chilled bowl, whisk the heavy whipping cream, granulated sugar, and vanilla until medium peaks form. The cream should look fluffy and hold its shape, but it should still be soft enough to spread easily. Medium peaks work best because they keep the whipped cream light without becoming grainy. If you are serving a mixed crowd, this layer is easy to adjust. You can spoon it more thickly for a richer dessert or keep it lighter for smaller portions in cups. This is one reason the no bake chocolate lasagna trifle is so popular for family events and parties.

4-Fourth Step: Make the ganache. Place the dark chocolate, heavy cream, and oil in a microwave-safe bowl. Microwave in short bursts, stirring in between, until the mixture becomes smooth and glossy. The oil helps the ganache stay shiny and easy to pour. Let the ganache cool slightly before adding it to the dessert. If it is too hot, it may melt the whipped cream layer. A short cooling time gives you a thicker finish that sits nicely on top.

5-Final Step: Assemble and chill. Assemble the trifle by layering the cookie crumbs, chocolate pudding, and whipped cream in your serving bowl. Repeat the layers until the bowl is full, finishing with whipped cream or pudding depending on the look you want. Pour the ganache on top once the dessert has had time to chill a bit. Cover the trifle and refrigerate for 6 to 8 hours, or until fully set. Right before serving, top with cherries and chocolate shavings if you want a polished finish. This dessert serves 10, so it is a great fit for gatherings, holiday dinners, and special events.