In a mixing bowl add room temperature butter and sugar. Mix for 5 minutes until light and fluffy, and lighter in color.
Add the vanilla and egg whites and mix well.
Add your flour, salt, and baking powder, folding in to just combine.
Add your champagne and if using fuchsia gel color and gently fold to just incorporate.
Evenly divide your batter between the two cake pans.
Bake for 25-30 minutes or until the tops are lightly golden and a toothpick comes out clean.
Allow cakes to cool completely before frosting
Yuzu Swiss Meringue
Add the egg whites and sugar to a glass bowl. With a hand whisk, whisk briskly for 5 minutes.
Place the bowl over a sauce pan of simmering water, creating a double boiler. The water should not touch the bottom of the bowl.
Whisk continuously for 5-8 minutes until the mixture is light and foamy and it reaches 160 degrees.
Gently pour the hot mixture into the bowl of your mixer. Mix on high for 10 minutes.
While the egg mixture is mixing, place a bowl with your yuzu chocolate over the pot of simmering water and slowly allow to melt, gently stirring.
Pour the melted chocolate into the fluffy egg and sugar mixture and mix for 5 more minutes. Your frosting should be glossy, thick, and luscious like marshmallow fluff.
Spread half of your yuzu Swiss meringue on one layer of your cake. Sprinkle with your berries.
Gently place the second layer on top and spread your remaining Swiss meringue over the top. Top with your remaining berries.
Snap a pic of your beautiful creation, slice, and enjoy!