Chocolate Mousse Icebox Cake Filled with Love

So what’s better than an icebox cake? A chocolate mousse icebox cake! Two desserts we all love so much, so it makes perfect sense to combine them and create a dessert for those of us who love to indulge in something wonderful. I created this dessert for Mamush, my love, for Valentine’s Day, but the truth is, it’s perfect for any day and any time.

After creating so many combinations that have become beloved favorites, like my Tiramisu Icebox Cake and later my Chocolate Mousse Tiramisu, here’s the new combination that’s going to become a star in your kitchen: a chocolate mousse icebox cake with decadent chocolate ganache.

Beyond the importance of using excellent chocolate to achieve perfect chocolate mousse, it’s crucial to use quality petit beurre biscuits and not the ones that haven’t seen a trace of butter. After all, Petit = small, Beurre = butter, which means we’re talking about small butter cookies… Think about that before you eat dairy-free Petit Beurre! 🙂

And to make this dessert more suitable for adults celebrating love, it’s worth fortifying both the milk you soak the petit beurre biscuits in and the ganache with a generous amount of rum. Its combination with the biscuits and chocolate mousse is simply perfect and makes this comforting dessert even better.

Chocolate Mousse Icebox Cake
Long Pyrex dish 25cm, height 7cm

Ingredients
For soaking the biscuits:
180g whole milk
30g rum

Chocolate Mousse:
125g whole milk (as fatty as possible)
240g dark chocolate 70%, chopped
30g egg yolks
220g egg whites
50g white sugar

Chocolate Ganache:
150g heavy whipping cream
120g dark chocolate 70%, chopped
20g rum

Assembly:
About 40g fine cocoa powder, sifted
About 250g high-quality petit beurre biscuits

Preparation
1. For soaking the biscuits: In a small bowl, mix milk and rum. Set aside.
2. Chocolate Mousse: In a small pot, bring milk to just below boiling.
3. Meanwhile, melt the chocolate in a double boiler (bain-marie).
4. Pour the hot milk over the chocolate and mix until smooth, add egg yolks and mix vigorously so they don’t curdle. Cool slightly.
5. Whip the egg whites and gradually add the sugar. Whip until you get stable peaks, but not too stiff.
6. Fold the egg whites into the warm chocolate mixture until you get a uniform and airy mousse, and proceed immediately to assembly.

Assembly
7. Line the bottom of the dish with a layer of petit beurre biscuits.
8. Moisten the biscuits (while they’re in the dish) with about 2-3 tablespoons of the milk and rum mixture.
9. Sprinkle a little cocoa over the biscuits (optional).
10. Pour half the chocolate mousse over the biscuits and smooth gently.
11. Arrange another layer of petit beurre biscuits on the mousse, moisten with the milk mixture, and sprinkle a bit of cocoa. Repeat with the remaining half of the chocolate mousse and another (third and final) layer of biscuits, which you moisten with milk and sprinkle with cocoa. Refrigerate for at least one hour.
12. Chocolate Ganache: In a medium pot, bring cream to almost boiling, remove from heat and pour over chocolate. Wait one minute and using a spatula, start mixing. It’s recommended to mix in the center of the bowl without lifting the spatula from the bottom to avoid air bubbles. Mix until all the chocolate is completely melted, add the rum, and mix to get a smooth ganache.
13. Pour the ganache over the top layer of biscuits and smooth.
14. Refrigerate for a minimum of 4 hours. It’s recommended to wait overnight before eating as the dessert’s flavors improve.
Tip: If you want to decorate the cake, you can create heart shapes on the ganache using a heart-shaped cookie cutter. Wait for the ganache to set, then gently mark with the cutter.

Bon-Appétit
Sharon