This is a great cake, perfect for Halloween parties, that is a take-off of the stand-by graveyard pudding. I noticed pudding is less popular than cake, and of course, cake is more suited for parties, especially those with kids. You can use your choice of cake flavor, but pay attention to the cookie crumbs you use in that case so they are compatible flavors. You also probably wouldn't want to use chocolate icing with a pumpkin cake, but if you wanted a pumpkin frosting, that would be good, or else use vanilla.You can use whipped cream to make the ghosties, but be aware that if you do this, the cake needs to remain chilled, and the whipped cream does try to sag and run after awhile (so don't do that too far in advance). The marshmallow ghosties are more durable at room temp. Those are often sold near displays of halloween candy, not necessarily by the bags of marshmallows.