Preheat your oven to 350°F (175°C).
Grease and flour two 9-inch round cake pans.
In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.
Add the eggs, one at a time, mixing well after each addition.
Stir in the champagne and vanilla extract, mixing gently.
In a separate bowl, whisk together the dry ingredients: flour, baking powder, and salt.
Gradually add the dry mixture to the wet ingredients, mixing until just combined.
Pour the batter evenly into the prepared cake pans.
Bake in the preheated oven for 25-30 minutes or until a toothpick comes out clean.
Allow the cakes to cool in the pans for 10 minutes before transferring to wire racks.
Once cooled, whip the heavy cream with powdered sugar until stiff peaks form.
Place one layer of cake on a serving platter and spread a layer of whipped cream on top.
Top with the second layer of cake and frost the top and sides with the remaining whipped cream.
Chill the cake for at least 30 minutes before serving.
