Mousse au Chocolat

Step 1

Chop the dark chocolate into pieces smaller than a grape and place them in a microwave-safe bowl.

Step 2

Add 2 tablespoons of butter and 3 tablespoons of water to the bowl with the chocolate.

Step 3

Microwave on 50% power for 90 seconds, then stir the mixture with a spoon until it looks completely smooth and glossy, with no visible chocolate chunks.

Step 4

Let the chocolate cool to room temperature by waiting 5 minutes, stirring once halfway through, until it no longer feels hot when you dip your finger in.

Step 5

Pour the 3 egg whites into a clean, dry bowl (even a tiny drop of yolk will stop them from whipping).

Step 6

Using an electric mixer on medium-high speed, beat the egg whites for 2 minutes until they turn foamy and white, with bubbles throughout.

Step 7

Sprinkle in 3 tablespoons of sugar and 0.25 teaspoon of salt, then continue beating for 2 more minutes until stiff peaks form — when you lift the beaters, the whites stand straight up and don't flop over.

Step 8

Pour 1 cup of cold heavy cream into a separate clean bowl and beat with the electric mixer on medium-high speed for 2 minutes until soft peaks form — the cream doubles in volume and looks fluffy but still slightly droops when you lift the beaters.

Step 9

Add the 3 egg yolks to the cooled chocolate and stir with a spoon until completely mixed and no yellow streaks remain.

Step 10

Pour the whipped cream on top of the chocolate mixture, then use a rubber spatula to gently lift chocolate from the bottom up and over the cream; rotate the bowl a quarter turn and repeat until no white streaks of cream are visible.

Step 11

Pour the whipped egg whites on top of the chocolate-cream mixture, then repeat the folding motion (lift from bottom, flip over the top, rotate, repeat) until no white streaks remain and the mousse looks evenly dark brown.

Step 12

Divide the mousse evenly among 4 serving bowls or glasses, spooning about 0.75 cup into each.

Step 13

Serve immediately, or cover with plastic wrap and refrigerate for up to 2 hours before serving.