From America's Test Kitchen Season 10: Triple-Chocolate Mousse Cake
Triple chocolate mousse cake is a truly decadent dessert. Most times, though, the mousse texture is exactly the same from one layer to the next and the flavor is so overpoweringly rich it’s hard to finish more than a few forkfuls. We set out to tweak this showy confection. By finessing one layer at a time, starting with the dark chocolate base and building to the top white chocolate tier, we aimed to create a triple-decker that was incrementally lighter in texture—and richness. For simplicity’s sake, we decided to build the whole dessert, layer by layer, in the same springform pan. For a base layer that had the heft to support the upper two tiers, we chose flourless chocolate cake instead of the typical mousse. Folding egg whites into the batter helped lighten the cake without affecting its structural integrity. For the middle layer, we started with a traditional chocolate mousse, but the texture seemed too heavy when combined with the cake, so we removed the eggs and cut back on the chocolate a bit—this resulted in the lighter, creamier layer we desired. And for the crowning layer to our cake, we made an easy white chocolate mousse by folding whipped cream into melted white chocolate—and to prevent the soft mousse from oozing during slicing, we added a little gelatin to the mix.
Serves 12 to 16
This recipe requires a springform pan at least 3 inches high. It is imperative that each layer is made in sequential order. Cool the base completely before topping it with the middle layer. We recommend Ghirardelli Bittersweet Chocolate Baking Bar for the base and middle layers; our other recommended brand of chocolate, Callebaut Intense Dark L-60-40NV, may be used, but it will produce drier, slightly less sweet results. Our preferred brand of white chocolate is Guittard Choc-Au-Lait White Chips. For best results, chill the mixer bowl before whipping the heavy cream. The entire cake can be made through step 8 and refrigerated up to a day in advance; leave it out at room temperature for up to 45 minutes before releasing it from the cake pan and serving. For neater slices, use a cheese wire or dip your knife in hot water before cutting each slice.