1. Make the Crust:

– Preheat the oven to 350°F (175°C).

– In a medium-sized bowl, combine the graham cracker crumbs, sugar, and melted butter. Stir until the crumbs are evenly coated with butter.

– Press the mixture into the bottom and up the sides of a 9-inch pie dish or tart pan. Use a spoon to gently pack the crumbs tightly.

– Bake the crust in the preheated oven for 8-10 minutes, until golden and slightly firm. Let it cool completely on a wire rack.

2. Prepare the Chocolate Mousse Filling:

– Break the dark chocolate into pieces and melt it. You can melt it using a double boiler or microwave (in 30-second intervals, stirring each time).

– Once the chocolate is melted, allow it to cool slightly.

– In a separate bowl, whip 1 ½ cups of the heavy cream with the powdered sugar and vanilla extract until soft peaks form.

– Fold the whipped cream gently into the cooled melted chocolate, being careful not to deflate the mixture. The mousse should be light and fluffy.

3. Assemble the Pie:

– Pour the chocolate mousse filling into the cooled crust. Smooth out the top with a spatula to create an even layer.

– Refrigerate the pie for at least 4 hours, preferably overnight, to allow the mousse to set.

4. Serve and Enjoy:

– Before serving, whip the remaining ½ cup of heavy cream and pipe or spoon it on top of the pie for decoration.

– You can garnish with shaved chocolate, chocolate curls, or fresh berries for an extra touch.