I have made this twice, and it has worked just fine. Avoid over-whipping. Very light and tasty frosting on a wonderfully dense chocolate fudge cake.
I couldn't get this to set at all. It was too soupy to use as a frosting. It tasted great, but not workable for my cake at all. I tried super high speed on my Kitchenaid for 10 minutes, I tried extra marshmallow, I even tried frozen whipped topping added in. Nothing worked. I am disappointed and will have to start over with a different frosting. I think I will try the creme de menthe.