The cake pan was sort of expensive, but not as expensive as buying a cake usually is, so I'm posting my pictures of the process in case someone else decides to be brave and try. (P.S. I didn't try to pipe the frosting on in stars, I used a rubber spatula and just normal cream cheese frosting instead of making butter cream.)
First, I just made the cake mix like the instructions on the back. And then I used Pam for baking (with flour in it) and sprayed the pan. I poured in the batter and spread it around with a spatula. Then I put it in the oven. It did take a little longer to bake, but the instructions for how long to bake it were on the inside of the pan when I bought it. (Being literate is definitely a blessing.) Once it came out of the oven, I let it cool in the pan for about 10 minutes and then I cut off the rounded part on the back to try to make it so it could lay flat on the pan. Then, I went around the edges with a rubber spatula and dumped onto the cooling rack. I left it on this rack for a little more than an hour, so it would cool well and not fall apart when I frosted it.
Then, I took a cookie sheet with a flat side and just slid it under the cake. You can use a cookie sheet and a cake board instead, but I already had the cookie sheet, and it worked well. Then, I sorted two cans of frosting into several bowls. I put about one whole can of frosting into a big mixing bowl and dumped in a whole bunch of red cake frosting food coloring. I didn't quite use enough, so it was still slightly pink, but that stuff gets everywhere, and I have an uncanny talent for huge messes, so I decided to quit while I was ahead and use the pink.
Then, in one of the smaller bowls, I put black food coloring. I did buy the black from the party store, too because it's almost impossible to mix black. I used a large amount of black for the small amount of frosting, partly so I wouldn't have gray and the black turned out alright. OK, so I'm really cheap, and I didn't want to get cake decorating stuff just for the mouth and eyes, so I used a plastic zipper bag and cut off the corner. (If you want to try this, I highly suggest from experience (see above about the messes?) that you get a brand name one that you know the zipper will STAY closed on.)
Then, I squirted it out of the bag onto the mouth. Then, I very carefully used a rubber spatula to make the red. It worked out well. I wanted it to be fluffy, so I purposely didn't try to spread it straight. I went different directions, and I kept pushing the spatula into the frosting and lifting it out. It turned out pretty well. Once the red was done, I added some yellow to it to make the orange for the nose. Then, I used a butter knife to spread the nose. I wanted it to be as smooth as possible. It didn't come out completely smooth, but I feel like I did well. Then, I used some white that I saved out and didn't color for the eyes. I used a different butter knife and spread the eyes. Then, I used my trusty plastic bag again and did the black spot on the eyes.
Ben knew at first site who it was. He pointed right to it, his smile went all the way across his face, and he said, "ELMO!" There are quite a few cake pans out there, so if you want to do a kids' b-day party, this was fun, educational for me, and cheaper than buying an Elmo cake from somewhere else. I'm thinking that next time I have a two year old b-day I'll try again with the Elmo. I'm thinking that for Jackie, we might get brave enough to try Tinkerbell. . . :)