Preheat oven to 350°F (175°C). Place the coconut in a single layer on a lined, rimmed baking sheet. Bake for 10 to 12 minutes, stirring every few minutes, until the coconut is toasted. Set aside to cool slightly.

Place the flour, sugar, and salt in a large mixing bowl, and stir to combine. Mix in the cooled coconut.

Add the butter and mix with a pastry blender, a fork, or your fingers until thoroughly combined. The mixture will be crumbly but should hold together when pinched.

Transfer the mixture to a 9-inch round pie plate or tart pan with a removable bottom. Press the crust firmly and evenly into the bottom and up the sides of the pan. Use a measuring cup, a spoon, or your fingers to press the crust into the pan.

Bake 15 to 18 minutes, or until the crust is golden brown. Set aside to cool completely.

Place the chocolate in a small saucepan. Melt over medium heat, stirring until smooth.

Remove from the heat and stir in the confectioners' sugar and vanilla. Transfer the mixture to a large mixing bowl. Allow to sit for 5-10 minutes.

Using an electric mixer with a whisk attachment, whip the cream in a separate bowl until soft peaks form.

Add about 1/4 of the whipped cream to the chocolate mixture. Stir until combined. Gently fold in the remaining whipped cream.

Spread the mousse evenly in the cooled crust. Top with more toasted coconut, if desired.

Cover and refrigerate at least 2 hours before serving.