My son picked Super Mario for his birthday theme. My problem is the unique style of cake he wants as the second tier. The bottom tier is a square RKT base with different levels decorating the sides. The top level is a one-up mushroom. The middle tier he wants is a "piñata" cake that's the question mark boxes which while playing give you power ups and gold coins, filled with gold coins to give to his friends after the cake is cut.  I am trying to offset the mushroom to minimize the weight directly on top of the center of middle tier. How can I add enough support or lessen the weight (RKT mushroom?) so the surprise tier does not collapse prematurely? plus anyone have good sturdy banana cake recipe. If your not a fan of Mario most people don't know he first appeared in Nintendo Donkey Kong video game. We  are paying tribute to that with banana cake with chocolate ganache if I can find a recipe for the cake. Most recipes I found have keywords like fluffy, moist, delicate describing them. While I can work around moist the words fluffy and delicate don't give me confidence while building a cube of cake with the center out of most of it.

I would use a set up with a top & bottom acrylic plates and the one acrylic  tube up the middle for the gold coin cake -- very secure -- no worries -- the tube is only 1.5" -- don't know how big you're making this -- but you can get as small as a 6" plate -- you can use a bigger plate on the bottom if you want for even more stability -- just whatever works on the top of the rkt cake -- you can cut the tube to the length you need -- maybe something like that -- or just plain sps would work too --

these are available elsewhere too -- it says the smallest is 8" but the 6" is in the list too so -- 

I dont know for the structure of your cake, Never done something that complex. For the banana cake recipe, this one is my absolute favorite of all time. Yes it is moist, but I would not describe it as fluffy or delicate. It is not super dense either as a banana bread could be. Well, to me it is just perfect! 

It's the recipe given by @Mbalaska in the post #7. The "Best ever banana pudding cake".

https://www.cakecentral.com/forum/t/778778/best-ever-banana-pudding-cake-recipe

You can omit the freezer thing if you prefer. Cake is very good even without it!

Now I want banana cake....

Ohh goody I just noticed that I got bananas ready for baking into bread or cake. I might have to try it tomorrow.

That banana cake rocks! It is delicious! You will love it :-)

but thinking about this more -- you need to make at least an 8" cake to use the acrylic tube in the middle thing or there won't hardly be enough room for the coins -- but just off top of my head i'd think at least a 10" would do best -- but depends on the size of your coins and all the other proportions

oh I forgot to post the link and while i'm at it  -- if you use the code discount15 you get a 15% discount

https://www.efavormart.com/search?q=acrylic+plate

and if you scroll down you will see the link for the tube

K8memphis, due  t  coin size I can find and the amount I putting in I was going to a 12 in size at least. plus easy for me to calculate how many layers of cake I need to use to obtain the cube shape. Thanks for the link, was going to ask but got distracted when answering posts.

perfect then if you go that way -- it's very secure

pictures pictures pictures 

I don't have a recipe to share but I have made many "pinata" type cakes - the last being a bag of (chocolate coin) money for my nephew.  A pound cake is the most stable kind of cake to me when you are hollowing out the middle.   Because the cake is less structurally sound with a giant hole in the middle even when it's filled with goodies.  Fondant definitely helps keep the shape together, too.  While a pound cake can be flavored as well but I'm sure not as much as something called the ultimate banana cake (!) but you can put bananas between the layers or a banana pudding between the layers.

Sounds like a fun project!

Theresa

Thanks Theresa for the information. Originally it was going to be chocolate which is my son's favorite cake flavor and have one up mushrooms that are vanilla. Maybe I should go back to that plan. Will see after I bake the banana cake today. Worse thing that will happen is I got a good banana cake recipe for my husband who like one of the local chain store's banana cake.

There's nothing wrong with a cake-experiment shdvl!  There are many worse things than having an extra cake ;)