Preheat oven to 350 degrees. Spray a 9-inch tart pan with nonstick baking spray.
Mix together the cookie crumbs and butter. Press evenly in the bottom and sides of the prepared pan. Bake for 8 minutes. Remove and cool.
Place the butter and chocolate in microwave safe bowl. Heat for 30 seconds. Stir. Heat for an additional 15-30 seconds, stirring often. Stir until mixed together and creamy.
Beat the eggs, cream, sugar, and vanilla until frothy.
Pour the chocolate into the egg mixture and beat in until smooth. Pour the mixture in the cooled crust.
Place a baking sheet on the oven rack under the tart in case of leaking butter. Bake the tart for 28-30 minutes. It will seem undone, but remove it and cool on a wire rack for one hour. Refrigerate at least 2 hours or until completely chilled.
Mix together 2 cups whipped topping and 1 cup cherry fruit filling. Spread the mousse on the top of the cooled tart.
Gently remove the tart from the pan and place on a serving plate. Pipe the remaining whipped topping around the edges of the tart using a piping bag and icing tip 1M.
Spread the remaining cherry fruit filling in the center of the tart. Add sprinkles, chocolate curls, and hearts for an added decoration, if desired.