Chocolate Buttercream and Marshmallow Fluff

I made two batches of cupcakes, both were chocolate sponge. One had a marshmallow fluff and coconut topping and the other had a plain chocolate buttercream topping with a sparkly purple flower. I have heard you can make a marshmallow icing which I plan to attempt at some point as I found the marshmallow fluff was incredibly sticky which made it impossible to pipe.