Chocolate-Orange Mousse

8 oz bittersweet chocolate, chopped fine
4 Tbs water
2 Tbs cocoa powder, preferably Dutch-processed
2 Tbs Grand Marnier
1 tsp instant espresso powder
2 large eggs, separated
1 Tbs sugar, divided
1/8 tsp table salt
1 1/8 cup heavy cream, chilled
3 2 inch x 1/2 inch strips orange zest

Bring the heavy cream to a simmer in a medium saucepan.

Remove from the heat and transfer to a measuring cup.

Add the strips of orange zest.

Cool until just warm, cover, and refrigerate overnight.

Melt the chocolate with the water, cocoa powder, and espresso powder in a medium heatproof bowl set over a saucepan filled with 1 inch of barely simmering water.

Stir frequently until smooth.

Remove from the heat.

Stir in the Grand Marnier.

Whisk the egg yolks, 1 1/2 teaspoons of the sugar, and the salt in a medium bowl until the mixture lightens in color and thickens slightly, about 30 seconds

Pour the melted chocolate into the egg mixture into the egg mixture and whisk until combined.

Cool until just warmer than room temperature, 3 to 5 minutes.

Using an electric mixer, whip the egg whites at medium-low speed until frothy, 1 to 2 minutes.

Add the remaining 1 1/2 teaspoons sugar.

Increase the mixed speed to medium-high speed and whip until soft peaks form when the whisk is lifted, about 1 minute.

Using the whisk stir about one quarter of the whipped egg whites into the chocolate mixture to lighten it.

Gently fold the remaining egg whites with a rubber spatula until a few white streaks remain.

Remove the cream from the refrigerator and discard the strips of orange zest.

If needed add more cream to ensure it measures 1 1/8 cups.

In the now-empty bowl, whip the heavy cream at medium speed until begins to thicken, about 30 seconds.

Increase the speed to high and whip until soft peaks form when the whisk is lifted, about 15 seconds more.

Using a rubber spatula, fold the whipped cream into the mousse until no white streaks remain.

Spoon the mousse into six to eight serving dishes or goblets.

Cover with plastic until set and firm, at least 2 hours or up to 24 hours.

The Complete America's Test Kitchen TV Show Cookbook 2001-2017. Page 788-789. U.S.A.: Penguin Random House, 2016.