I want to make a bath tub cake dummy, but can I carve a cake dummy into the shape of a bathtub? Should I use a large square for this? I have never made a dummy before, so what do I frost it with? can I use fondant? Help please!

To help, I need a little more information. What size do you want the tub to be, and what type of foam are you wanting to use? Regular cake dummy Styrofoam is not going to carve well because it is made up of small pieces of foam, which have a tremendous amount of static electricity. This stuff goes everywhere and is a bear to clean up! The only kind of foam that might work would be florist foam and it's still going to be difficult to carve a tub shape out of it.

The type of frosting you use will depend on if it's a hollow tub or one that appears to be full. Fondant does not stick well to foam unless you put it on upside-down and let it dry completely. Buttercream would work better in this case.

Is this for a customer that just wants to have it as a memento or are you working on a competition cake? If it's for a customer, charge plenty. The amount of work going into just carving the foam will very time consuming. If it's for a competition, then it probably is supposed to be real cake with at least 3 in-progress photos. For this, use a good pound cake and again with buttercream. It's not likely that you would make a real cake for someone in which the fondant had to dry several days before finishing the decoration.

This is a tough shape. I hope you post pictures when you get it done.

Michele

Well, it is a bit complicated, but it is for a baby shower. I need dummy cakes anyway, and the dummy was my idea, not the clients. I would like to do pulled sugar to make the water look more realistic. The cake does not need to be hollow. Should I use rice crispie treats and mold them? will they hold up?

Rice Krispies would be a great way to go. If you have the large egg mold from Wilton, you could use that as a basic shape and then go from there.

When making the Rice Krispie treats, don't use butter. This will help them to set up quickly and retain its shape.

Michele

I would use rice cereal! Easy to mold and cover!

I have heard that you can use puffed rice cereal (the unsweetened plain kind) and mix it with royal icing and mold and form it. Never tried it, but I thought I would if I ever needed a dummy cake.
You should be able to frost it in any normal icing. Just keep in mind how long it is supposed to last because icings with butter and milk and even shortening will eventually go rancid.
You should be able to cover in fondant , no problem, it works best if you ice the dummy first with a thin layer of icing to help the fondant stick and go smoothly around edges and corners.
GOOD LUCK!

thanks so much! but, if I don't use butter, what should I use-crisco, or just the marshmallows?