Ok, so I am having a Fall Mary Kay Party next weekend and am working on some recipes to see how they work. Here is the first recipe I tried.
http://www.thekitchn.com/recipe-pumpkin-2-159672

I rolled them into balls to make them look like pumpkins, but then as my hands were covered with pumpkin/marshmallow goo, I remembered this party is for adults, and adults don't usually care what their food is shaped like. We'll see how well they stay together in "pumpkin" form before final shape decisions are made.