Reduce the champagne by placing the champagne in a saucepan over low to medium-low heat, whisking occasionally until about 2 tablespoons remain (it will turn a light golden-brown color in about 20 minutes). Set aside and let cool.
Add the heavy cream to the bowl of a stand mixer and beat on high for 3-4 minutes until stiff peaks form.
Add the confectioners' sugar and salt and mix again.
Drizzle in the champagne reduction and vanilla extract and mix again.
Recipe by Her Modern Kitchen at https://www.hermodernkitchen.com/new-years-eve-pinata-cake/