Prepare the crust by buttering a 10-inch pie plate. Combine gingersnap crumbs and melted butter in a bowl until moistened. Press into the pie plate and refrigerate for at least 30 minutes.

In a saucepan, combine cranberries, sugar, and water. Bring to a boil over medium heat and cook for about 15 minutes until thickened. Cool slightly and puree until smooth.

In a mixing bowl, add the cooled cranberry puree, cream cheese, and vanilla paste. Blend with an electric mixer until smooth.

Gently fold in Cool Whip with a spatula until no streaks remain, keeping the mixture light and airy.

Spread the mousse evenly into the chilled crust. Cover loosely and refrigerate for at least 4 hours or overnight.

Before serving, top with whipped cream and optional garnishes. Slice and enjoy!