Combine crushed gingerbread cookies and melted butter in a bowl, then press into the bottom of a 9x13 inch baking dish.
Beat together powdered sugar, softened cream cheese, and vanilla extract until smooth, then spread over the cookie base.
Whisk together chocolate pudding mix and milk until thickened, then spread over the cream cheese layer.
Top with whipped topping, smoothing it out evenly, then cover and chill for at least 4 hours or overnight.
Sprinkle crushed peppermint candies on top before serving, then cut into squares and serve.