Sometimes you eat something that transports you to heaven, with angels blowing on trumpets and rays of golden light. This chocolate mousse is so light and fluffy, to call it a cloud of chocolate would be too heavy. It’s a dream about chocolate, set to angelic music.
The ingredients are very simple. The keys to success are all in the process. Don’t worry–it’s still easy. A dessert you can whip up in a few minutes. BUT plan ahead. It should be made at least a day ahead, if not two. The air bubbles grow, making the mousse even lighter.
First, you should know the different Schools of Chocolate Mousse. There are the Whipped Cream School, the Egg White School and the fence-straddling Cream-and-Egg School. An all-chocolate French cookbook (Le Chocolate, from Madame Figaro magazine) has FOUR chocolate mousse recipes, in the Cream and Cream-and-Egg camps. A recipe on Cuisine Larousse, as well as one by Alain Ducasse, uses cream, but both count on the egg whites to make the foam (mousse means foam). The Whipped Cream School basically makes something like chocolate Cool Whip–OK for what it is, but lacking the seemingly contradictory qualities of airiness and creaminess that makes chocolate mousse so special.Some recipes mix cream with the chocolate–like ganache–or butter with the chocolate, or both cream and butter. The point is to increase the fat content, for that creamy quality, rather than to whip the cream. The egg whites are what provide the fluff, which is airier and longer lasting than whipped cream. This recipe uses only butter, which is 82% fat; heavy cream is only 36% fat.
This recipe is squarely in the Egg Camp and comes from the great-grandmother of our friend R., who provided the very important passed-down-through-generations tips that make all the difference. (When I asked him about cream in chocolate mousse, he made a terrible grimace!) Another special point is that this recipe uses the egg yolks (some in the Egg School use only the whites), adding to the creamy factor in the way that some ice cream uses custard–yolks are 27% fat.
Before some of you faint over the idea of eating raw egg whites, even chocolate ones, let me point you to Santé Publique France, which in 2015 counted 141 cases of salmonella, with 20%, or 28 cases, linked to eggs, out of a population of 67 million. On the French government’s National Agency for Health Safety of Food, the Environment and Work’s page about salmonella, it cautions that recipes using raw eggs should be kept cold and eaten within 24 hours. That said, chocolate mousse is even the third day. A risk I’m willing to take (though waiting is hard!).
6 or 7 eggs, depending on their size
200 g (7 oz.) butter, cut into small chunks
200 g (1 cup) granulated sugar
200 g (7 oz or 2/3 cup) dark chocolate (at least 60% cacao, which won’t taste like dark chocolate in the end; if you like darker, up the percentage), broken into small bits
Turn on the oven to just warm (60 Celsius or 140 Fahrenheit). Put the butter and chocolate into an oven-proof pan or dish and let it melt slowly in the oven, until the butter and chocolate are very soft but not liquid. R.’s advice: the oven heats the ingredients more gently than the microwave and more homogenously, without having to stir a lot, than a double-boiler on the stove.
While it’s melting, measure the sugar into a large bowl. Add the egg yolks, separating the whites into a separate mixer bowl for beating. Mix the yolks and sugar by hand (important! otherwise it comes out too “hard”) until the mixture is white.
Stir the butter and chocolate so they are completely integrated, then pour into the yolk/sugar mixture. Mix that well.
Using an electric mixer, beat the whites until they are stiff. You can turn it on while you’re mixing the previous step but keep an eye out that you don’t overbeat the whites or they’ll collapse. Anyway, you want the chocolate mixture to cool down before adding the egg whites, or the heat will deflate the eggs and make the mousse too dense. The chocolate mixture just has to be warm enough that it doesn’t get hard.
Fold the whites into the chocolate mixture in batches. Use a wooden spoon or a spatula, and gently guide the batter from the bottom to the top, in one direction! You want the whites to be integrated into the batter, but it’s more important not to have streaks of chocolate mixture vs. trying to get rid of all the little blobs of whites.
That’s it. You can put it into a large serving bowl or into individual bowls. It makes about 10 half-cup servings (small ramekins). If you want to double the recipe, it’s better to do it twice, because you risk over/under beating the egg whites if the volume is too great.
Refrigerate as long as possible. At least three hours, but better is overnight or up to two days. If you have anything smelly in the fridge, cover the mousse tightly with plastic film.