A simple from-scratch lemon cupcake has blackberry buttercream frosting. This cupcake is a refreshing hit! Garnish each cupcake with a blackberry or a pinch of. Last week, I got to escape the heat and go to my hometown of Fort Wayne, Indiana. Fort Wayne is not a bustling metropolis, but it beautiful in. A delicious and light vegan cupcake recipe topped with a sweet blackberry buttercream frosting. The perfect combination of lemon and blackberry! It's like a party in your mouth!. A delicious and light vegan cupcake recipe topped with a sweet blackberry buttercream frosting. A month or so, my good friend Jamie (aka my cupcake groupie) mentioned that she'd seen a lemon cupcake with raspberry frosting over on.