First off, we had to buy the cake (client's request) and I made the topper. The "21" is RKT covered in fondant. My wife added the flowers. The fondanting of the "21" was fairly difficult, but I ended up doing a long strip to do the egding then cut out the front and the back of the numbers and used clear vanilla to glue/blend the edges. It was hard to see the seams afterwards, but there were still some issues. I think I rolled it out too thin because RKT bumps were showing despite a coat of buttercream.