1. Preheat oven to 350 degrees Fahrenheit (175 degrees Celsius).
2. Spray a tart pan or pie plate with cooking spray and press the cookie dough into it and up around edges. Bake for 30–40 minutes or until done.
3. Remove from oven and use a spoon or 1/4-cup measure to press down the center of the tart and up on the sides, making it a tart shell with sides.
4. Melt the chocolate with two tablespoons whipping cream in a microwave or over a double boiler. Beat remaining whipping cream and fold in the melted chocolate mixture. Spoon or pipe mousse into the tart shell.
5. Refrigerate for at least one hour before serving.