1/2 cup Whole Milk 2 tablespoons Piment d’Espelette
For the Chocolate Mousse: Combine the milk and piment d’Espelette in a small saucepan. Cover and bring to a simmer over medium heat. Remove from the heat and set aside for 30 minutes to infuse the milk.
Stir the chocolate in a large bowl set over a saucepan of simmering water until melted and smooth. Strain the milk mixture through a very fine-meshed sieve and into the melted chocolate, and stir to blend. Discard the solids in the strainer. Set the chocolate mixture aside until cool to the touch, about 15 minutes.
Using an electric hand mixer, beat the egg yolks, melted butter, and 2/3 cup of the powdered sugar in a medium bowl until light and airy. Using an electric stand mixer with the whisk attachment, beat the egg whites with the remaining 2/3 cup of powdered sugar in the mixer bowl until soft peaks form.
Using a large rubber spatula, fold the egg yolk mixture through the cooled chocolate-milk mixture. Gently fold in half of the whipped egg white mixture to lighten the chocolate mixture, then fold in the remaining egg white mixture.
1 1/3 cups Heavy Cream
Beat the cream in the same large mixer bowl with the electric stand mixer until thick soft peaks form. Fold the whipped cream into the chocolate mixture. Be sure not to overmix the mousse in order to ensure it retains a light airy texture. Cover and refrigerate until cold, at least 3 hours and up to 1 day.
1/4 cup good-quality Extra-Virgin Olive Oil 2 Oranges (zested with a Microplane)
For the Orange Olive Oil: Combine the oil and orange zest in a food processor and blend for 1 minute. Transfer the oil to a container and store in the refrigerator.
Spoon the mousse into wide shallow bowls. Drizzle the oil over and around the mousse.