The Berry Best of Cakes: Blackberry-Lime Delight!

Blackberry Buttercream Frosting Instructions:

1. Whip the butter until creamy, then gradually add the powdered sugar and vanilla extract.
2. Incorporate the egg whites and blackberry puree, coloring if desired, to achieve a smooth frosting.

Now, let’s assemble our cake and add the finishing touches that’ll make your dessert truly stand out!