So this is what I came up with for a friend's birthday.
While the cake is cooking, mix up your favorite brownie batter. The fudgier the better.
When the cake comes out and cools, turn it out on a cooling rack and then put the brownies in one of the 9" rounds.
As the brownies cook, crush one package of grahams and add butter and a little sugar till it is holding together. Now you have to wait. The waiting is the hardest part.
I found that taking the brownie out of the round pan was tricky so I just sort of molded the brownie back together on the bottom yellow cake. But before that you need to add a layer of marshmallow creme with a little buttercream icing to make it easier to spread. Beware..super sweet layer!
Then add the brownie layer, then mold the graham layer ontop of that. Then another marshmallow creme layer then the top layer.
My marshmallow creme layer was to runny, hence the drip off. It would be pretty if it was thicker, also. I kind of liked how you were able to see the layers though. Let 'em know what they're getting into, right?