This chocolate mousse cake ticks a lot of boxes—big, grand, ideal for the holidays, and just enough of a challenge to ensure you feel accomplished. The one-bowl chocolate cake layer is dense and deeply fudgy; the mousse is airy and light; and the thin slip of ganache on top brings it all together. No matter what kind of year you’ve had, this dessert is the way to cap it all off.

Making the mousse alone will teach you three foundational pastry techniques, and they’re all hidden in plain sight. It starts with a crème anglaise; adding that to chopped chocolate yields a crémeux, and folding in whipped cream turns it into a mousse. Magical. The cake can be easily made from start to finish in the space of a morning, but can be split up further to fit your schedule. Bake the chocolate cake layer and chop all the chocolate on the first day; make the mousse and assemble the cake the following.

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