I used three different pan sizes for the cakes; mini muffin, regular muffin, and ramekin. The ramekin one was definitely my favorite. It was the perfect ratio of rhubarb and cake. Also, it had a large surface area to plop a dollap of whipped cream on top. The juices from the rhubarb took it's sweet time as it slowly seeped into the cake and gave it a nice pang of sourness. And even though, I don't like the consistency of the cake, I thought it was very nice when you have only a small layer of it. The muffin pan ones had way too much cake and not enough rhubarb.
Though I have to say, no matter what pan size I used, the cakes looked really ugly. When I flipped my first batch of cakes over, I was so sad. They were so chock full of crevices, it gave me the chills. BLEHHH.....I think next time I'll just frost the whole baby cake with whipped cream.
For the recipe, check out Erin's blog, When in Doubt...Leave it at 350 or better yet, get a copy of Baking with Julia and join in the fun! Also, if you're interested in how other TWD baker's made their cakes, check out the blogroll!