STEP 1: Prepare the Chocolate Cake Layers

Start by preheating your oven according to the instructions on the chocolate cake mix. If you are making the cake from scratch, follow your recipe for a standard chocolate cake.

Prepare the cake mix by combining the water, vegetable oil, eggs, and vanilla extract. Follow the directions on the cake mix box (or your homemade cake recipe) to mix the batter.

Grease and flour a cake pan, or line it with parchment paper. Pour the batter into the pan and bake for the time specified in the recipe (usually around 30 minutes for a standard cake pan). Use a toothpick to check for doneness—if it comes out clean, the cake is ready.

Once the cake is baked, allow it to cool completely before cutting it into small cubes. This step is crucial to prevent the cake from falling apart when assembling the trifle later.

STEP 2: Prepare the Double Chocolate Mousse

While the cake cools, it’s time to prepare the double chocolate mousse. Start by melting the dark chocolate and milk chocolate. You can melt the chocolate in a microwave-safe bowl in 30-second increments, stirring in between, or use a double boiler to melt the chocolate gently over simmering water.

Once the chocolate is fully melted, set it aside to cool for a few minutes.

Next, in a large mixing bowl, whisk the heavy cream and powdered sugar together until soft peaks form. Add the vanilla extract to the whipped cream and continue beating until stiff peaks form. Be careful not to overwhip the cream.

In a separate small bowl, dissolve the gelatin (if using) in warm water and let it sit for a minute. Add the dissolved gelatin to the melted chocolate and stir until smooth.

Once the chocolate mixture has cooled slightly, gently fold in the whipped cream. Start with a small portion of the whipped cream and mix until fully incorporated, then fold in the rest. The goal is to keep the mousse light and airy, so be gentle during this process.

Once the mousse is prepared, set it aside to chill slightly while you prepare the whipped cream topping.

STEP 3: Make the Whipped Cream Topping

To make the topping, whisk together heavy cream, powdered sugar, and vanilla extract until stiff peaks form. This whipped cream will top the trifle just before serving, adding a smooth and creamy finish.

STEP 4: Assemble the Double Chocolate Mousse Trifle

Now that all the components are prepared, it’s time to assemble the trifle. In a large glass trifle dish (or several smaller individual cups), layer the dessert starting with a layer of chocolate cake cubes at the bottom.

Next, add a generous layer of the double chocolate mousse on top of the cake. Smooth it out with a spatula to ensure an even layer. Continue layering the cake and mousse, alternating until you run out of ingredients. Depending on the size of your trifle dish, you should aim for 2-3 layers of each.

Once the mousse has been layered, top the trifle with a dollop of the whipped cream topping. Use a spatula or the back of a spoon to smooth it into an even layer across the top.

STEP 5: Chill the Trifle

Place the trifle in the refrigerator and chill for at least 2 hours, or overnight if you want to make it ahead of time. This chilling time allows the layers to set properly, making the dessert easier to serve and enhancing the flavors.

STEP 6: Garnish and Serve

Just before serving, garnish the top of the trifle with shaved chocolate, chocolate chips, or a handful of fresh berries. You can also add a few mint leaves for a refreshing touch and a pop of color. These simple garnishes will elevate the trifle’s appearance and add a burst of freshness to the rich chocolate layers.

Serve the trifle in large spoonfuls, ensuring each serving gets a bit of cake, mousse, and whipped cream for that perfect combination of textures and flavors.