This two-ingredient mousse tastes like a fluffy, whipped, lightly sweetened, extremely intense chocolate bar. In a bowl. Need I say more?
Traditionally, chocolate mousses are made using cream or egg whites, and their volume and thickness is achieved by whipping air bubbles into them. In contrast, this mousse achieves its smooth texture via an altogether different mechanism: the chemistry of cocoa butter. Cocoa butter is solid at room temperature. But if you get the proportions just right, you can create a perfect mousse-like texture by adding just enough water to melted chocolate so it only partially solidifies as it cools, creating a mousse-like texture without the help of air bubbles.
I would actually classify this as a whipped water ganache rather than a mousse, if I were going to get technical about it. Water ganache is the black coffee version of traditional chocolate ganache: strong, dairy free, slightly bitter and super stimulating.
Recipe: One Ingredient Dark Chocolate Mousse
Adapted from Melissa Clark’s recipe for the New York Times
Makes one generous serving
2 oz good dark chocolate, chopped into small pieces
1.6 oz hot water (approx. 3 tbsp + 1 tsp)
Optional variations: I recommend adding a pinch of sea salt to the hot water before melting the chocolate. Alternatively, try flavoring the mixture with a few drops of peppermint oil or vanilla extract, or substituting coffee for the water to get a nice mocha flavor.
Serving recommendations: This would taste great over fresh berries, with a dollop of whipped cream or crème fraîche on top. But it’s pretty great on its own, too.
Mix the chocolate and water in a small bowl and microwave on high for 30 seconds. Stir. If the water feels hot to the touch and the chocolate is melting easily, you’re done with the microwave. If you still notice chunks of chocolate in the water, microwave the bowl for another 10-20 seconds. Whisk until the chocolate is completely dissolved and no graininess remains (this step is very important for a silky result).
Place the bowl of liquid chocolate in a shallow ice bath.
Using an electric whisk or egg beaters (an immersion blender would probably work too, although I haven’t tried it), whisk the chocolate as it cools. After a few minutes you should begin to see its texture thickening modestly.
Stop mixing and remove from ice bath once the mousse has reached the thickness of softly beaten egg whites.
Btw: If the chocolate mixture cools too much it will develop a texture like that of chocolate frosting (you can see an example of this in the picture below). If you accidentally over-thicken it, try whisking in another teaspoon of hot water.