Welcome to the Cake Decorators Q&A

asked February 20th 2018

Disney Castle

Hi again
I have started to try & calculate how much butter cream I would need to make . I used your calculator & I just want to confirm a couple of things .
Your calculator for 4 X 35X 10 cms says I need 11,556g for 2 layers , I assume that means it will cover sides , tops & 2 layers in the cake ?
I also calculated 16 X 10X10cms 2 layers needing 6384 g for as above ?
If I need 17,940g in total does that mean I need 17kgs of icing sugar & 9kgs of butter ?
I also calculated for sugar paste 4X35X10cms round cakes I would need 5840g & 16X10X10cms 8640g ( assuming that covers sides & tops ) + for a board 45 cms square I have allowed 3 kgs therefore in total needing 17,480g of sugar paste is this correct , it all seems such a lot ?
Thanks for your help , I am starting to realise the scale of this project !
Kind regards


Hi Tina

I'm not able to look at all the figures at the moment and will address your question when I can look at the figures carefully. I didn't want to leave your question unanswered so please bear with me. I'm sorry for this inconvenience, I'll get back to you as soon as possible. 🙂


Hi Tina

I apologise for my late reply. I will try and address your question point by point.

1... Buttercream.

The cakes which you are baking are very large and you will need the amount of buttercream calculated. However, the total refers to the total amount of buttercream, not the icing sugar. The requirements are, 12k sugar and 6k butter. Obviously these are approximate figures depending on how generous you are with your filling and covering. If you are using a large domestic mixer, it will only be possible to make up 5k at a time. Therefore, I suggest that it may be more practical to make up a batch to fill and cover one cake and see whether there is sufficient or too much. This will give you a better idea of how much is needed in practice.

2... Sugarpaste

The figures which you have quoted for the fondant appear to be of the correct order. However, the amount you actually need will depend on the brand of fondant which is being used and what thickness it will be rolled out to. Again, it may be more practical to cover one cake first to seehow much you have used.

As always the figures given in the charts are not prescribed amounts, they are merely a guide. Figures have taken from those used by Paul in past tutorials. I would be grateful if you read the full blog which links to the tutorial.


Hi .
Thanks for the info .
I have just tried to make Mrs Jones madeira 35cms cake with white chocolate . I added 600g of melted white chocolate to the other ingredients normally used .
I thought it was cooked wooden skewer clean , the cake was lopsided & only half of it cooked properly .
How much white chocolate should I use , is it possible with this type of cake ? How long would it take to cook , please ?
Thanks for your help .


Hi Tina

Mrs Jones' madeira cake recipe doesn't specify white chocolate as an ingredient. The addition of the white chocolate is probably the reason why your cake failed. Ingredients need to be carefully balanced, taking into account how they would change the texture of the end result and how the process of baking affects the interaction beween the those ingredients. Baking is a science where calculations can make or break a successful outcome.
If you would like to try a sturdy white chocolate cake with exceptionally good reviews, try this:

White Chocolate Mud Cake


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