Step-by-Step Instructions

• Preheat your oven to 350°F (175°C).
• In a medium bowl, combine chocolate cookie crumbs, melted unsalted butter, and granulated sugar. Mix thoroughly until it resembles wet sand.
• Press the mixture evenly into the bottom and up the sides of a 9-inch tart pan. Bake for 10 minutes, then let it cool completely.
• In a microwave-safe bowl, melt the dark chocolate in 30-second intervals until smooth. Allow it to cool slightly.
• Whip 1 cup of heavy cream until soft peaks form. Fold this into the cooled chocolate until no streaks remain.
• In another bowl, beat the egg whites with a pinch of salt until medium peaks form. Gradually add ¼ cup of sugar until stiff peaks form.
• Carefully fold the beaten egg whites into the chocolate mixture.
• Add the peppermint extract and fold until evenly combined.
• Spoon the mousse into the cooled tart shell, smoothing the top with a spatula.
• Refrigerate for at least 4 hours until set.
• Whip the remaining 1 cup of heavy cream until soft peaks form and spread it over the set mousse layer.
• Garnish with crushed peppermint candies and chocolate shavings or curls before serving.