What to do with leftover champagne

So I need to preface this by saying we chose this recipe before we bought the champagne, bought pink champagne just so the cupcakes would be pretty, and then had to make a point to save some champagne to use for the cupcakes.  Leftover champagne is not something we are familiar with.  You need to be very careful when mixing the cupcakes, ours got a little tough.

Recipe: Pink Champagne Cupcakes with Pink Champagne Buttercream Frosting (from Gimme Me Some Oven)
Ingredients:
Cupcakes:
2 3/4 cups all purpose flour
3 tsp baking powder
1 tsp salt
2/3 cup butter
1 1/2 cups white sugar
3/4 cup champagne
6 egg whites

Frosting:
3 1/4 cups powdered sugar (we didn't use this much)
1 cup butter, at room temperature
1/2 tsp vanilla extract
3 tbsp champagne, at room temperature

Directions:
Cupcakes:
Preheat oven to 350 deg F and line cupcake pan with paper liners.

In a large bowl, cream butter and sugar until light and fluffy.  Sift flour, baking soda and salt, and then blend into creamed mixture alternately with champagne.

In another large clean bowl, beat egg whites until stiff whites form.  Fold 1/3 of the whites into the batter to lighten it, then fold in remaining egg whites.  Fill the cupcake liners about 2/3 full.

Bake at 350 deg F for 20 minutes.

Frosting:
With an electric mixer, beat together sugar and butter (add only some of the sugar to start, so you can taste for sweetness).  Mix on low until well blended, and then on medium for another 2 minutes.  Add vanilla and champagne, beating on medium for another minute.