Do you have any tips or pointers to offer? I am making a Birthday cake for a friend and I want to try a style that I've seen here on CC. It is a piece of cake cut out and stacked back on top of the layer cake.

Is the "piece" placed on a board or anything before putting on top? I'm so afraid it's going to fall over. Actually, I think it may fall over when I try to ice the cut sides!

I need your help!

I am using buttercream for this one. But I do have fondant on hand if needed.

I would definitely put the slice on a board cut to fit and would put a couple of dowels (straws) under the slice. If you can't get a grip on the slice to ice it, maybe you can use a bamboo skewer to stabilize it, then push the skewer through to the bottom cake board after you have stacked - just let that be the "center dowel" that secures the slice to the rest of the cake.

I made one of these kinds of cakes and I did put a small board under the "slice" I made sure there were supports underneath and then I doweled through the slice, down through the entire cake. I traveled with it 15 miles to the party with a husband driving who has no regards for bumps and the cake was perfectly fine!