Preheat oven to 350 degrees F and line mini muffin tins with cupcake liners.
Combine the sparkling wine with the vanilla and almond extract.
Whisk the egg whites until stiff peaks form, set aside.
Cream the butter and add sugar and lemon zest, beating until it’s light and fluffy.
Mix the flour and baking powder and slowly add 1/3 to the butter mixture, stirring to combine. Then add 1/3 of the champagne mixture and alternate between the two until they are all incorporated.
Gently fold the egg whites into the batter.
Fill cupcake liners 3/4 full and bake for 15 minutes or until a toothpick inserted into the center comes out clean.
For the frosting, cream the remaining butter and powdered sugar together with the remaining vanilla and St-Germain, beating until light and fluffy. Fill a piping bag with the frosting, and frost the tops of the cooled cupcakes. Decorate with gold sugar pearls.