Ben & Holly attempt to bake a Mooseberry fudge cake using Grandma holly's recipe, unaware that the raw cake batter is actually a revolutionary rocket fuel. While attempting to light the old-fashioned oven holly ignites the first layer, launching the oven to the Moon. In order to retrieve the appliance they build their own rocket ship and use the remaining cake layers to propel them to the moon and then back to Earth. Upon their return, the U.S. government places holly in charge of "elf" research and he sets about to recreate the cake recipe, half of which was destroyed in the initial explosion. Two Moon Men, Gidney and Cloyd, arrive to prevent holly from recreating the formula, as they fear an invasion of tourists