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asked June 25th 2018

Buttercream recipe for rainbow cake

How much buttercream will i need for a 8" rainbow cake with 6 layers
I normally do a 2:1 ratio for a standard cake but I'm thinking of replacing half the icing sugar with royal icing so it survives the heat and travelling. Does this sound ok?
Any other advice welcome as it's my first time doing one!


Hi scarr

A lot of people do replace icing sugar with royal icing sugar during hot weather to stabilise the frosting. If you do half and half you would still use the same ratio as you are doing normally. To work out how much you need, please take a peek at the buttercream filling and covering chart here:

Hope this helps.

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