The process of making a classic chocolate mousse is enough to make anyone, amateur or expert, a little twitchy. It starts with a chocolaty egg custard, which, in and of itself, is notoriously finicky. The eggs can scramble or make the base lumpy, while the chocolate can easily seize if it gets too hot. Then you fold in whipped cream. This step also makes me nervous, even with all my years of practice, because overmixing will quickly deflate your mousse.But there’s an easier way to make mousse, and I’m sharing it with you. Rather than starting with a custard base, I just melt chocolate in hot heavy cream. Then I whisk in cocoa powder to make it intensely chocolaty, and espresso powder, which adds lots of personality. Once the chocolate cream cools, I tuck it into the refrigerator until it’s well chilled. But here’s the genius part: I whip the chilled chocolate cream until just stiff. Done!SIMPLEST CHOCOLATE MOUSSE is excerpted from JUST COOK IT © 2018 by Justin Chapple. Reproduced by permission of Houghton Mifflin Harcourt. All rights reserved.
In a medium saucepan, bring 2 cups of the heavy cream just to a simmer over medium-high heat. Remove from the heat and add the chocolate chips. Let stand for 2 minutes, then whisk until smooth. Whisk in the cocoa powder, instant espresso, and salt. Transfer the chocolate cream to a large bowl and let cool completely. Cover with plastic wrap and refrigerate until chilled, about 1 hour.
Using a handheld mixer, beat the chocolate cream until smooth and holds stiff peaks when you lift the beater out of the bowl. Do not overbeat the cream because the fat will begin to separate and it’ll look curdled (see Note)—you’re making mousse, not butter! Spoon the chocolate mousse into bowls or glasses and refrigerate until ready to serve.
In another large bowl, using the handheld mixer, beat the remaining ½ cup heavy cream with the vanilla until smooth and holds a soft peak when you lift the beater out of the bowl. Spoon the whipped cream on top of the chocolate mousse and sprinkle with shaved or grated chocolate. Serve cold.
If you happen to whip the cream a little too much, very gently fold in cold heavy cream, 1 tablespoon at a time, until the mixture is creamy again.