Well I don’t know about anyone else but I am overly anal about sharp edges on fondant and have spent a good few months perfecting it and I can now get sharp edges on ganache and buttercream. The buttercream is a bit more fiddly but certainly still doable.
Here is a cake I did recently using ganache:
Here is a cake I did recently using buttercream:
Firstly, the best method is to use ganache, hands down it’s the best medium and for this you want just a straight ganache, not a pouring ganache and not a whipped ganache. Here are the specifics:
Your chocolate ideally should be the best you can find and the cream is specific to the country. So far I know for a fact that if you live in the UK (like me) use Whipping Cream ONLY. In the USA using Heavy or Heavy Whipping Cream and in Australia use Pure Cream. Whatever you use it has to have a fat content of 35%. So the ratios are as follows:
Dark Chocolate Ganache: 2 parts dark chocoalte to 1 parts cream
Milk Chocolate & White Chocolate Ganache: 3 parts chocolate to 1 part cream
If you are using ganache, I cover my cake with it (using the upside down method – I use a mixture of two techniques – if you want to know how I do this, I’ll explain), then I put it in the fridge to get really solid. When I am ready to cover it, I bring it out of the fridge and give it a light brushing with a pastry brush that has been sitting in boiling water – you don’t want too much water, just enough to make it stick. Once you’ve done that, leave it out of the fridge while you roll out your fondant. The trick is to get it really very thin. I roll mines to about 2/3mm thick – no thicker!! Now, because I spend ages perfecting my ganache like below, when I cover it with my fondant, it is pretty much straight away really very sharp:
Now, once covered, I do a rough smoothing, just to make sure there are no air bubbles etc – I put my cake back in the fridge. Now the fridge isn’t essential, but I prefer it because I like working with firm fondant for the next step. The next step is to take two pieces of thick acetate (I use 500 micron that took me ages to find and was really expensive! but that’s because I warned you of my super anal’ness lol) – you want to use your acetate to go round the top edge of the cake and with one piece of acetate on the side of the cake and one piece on top, go round the cake and slide the acentate together to sharpen the edges. As I say this is much easier when the fondant has firmed up in the fridge, because otherwise it’s easy for the acetate to dig into the fondant and rip it, especially if you are like me and have hands like a panel beater lol.
Now with buttercream, you MUST use an all butter, buttercream – I only use Swiss Meringue Buttercream – the reason for using only butter (never shortening) is that the butter sets up solid in the fridge and shortening does not. So follow the same procedure for the ganache, but for me, I find the fridge step after covering with fondant, essential, because when you are smoothing the fondant, the buttercream starts to melt really easily and really quickly. So when I take it out of the fridge to smooth with the acetate, I sometimes have to smooth a bit and put it back in the fridge to firm up again and keep repeating this until the cake is as I like it.
Now with all fondant covered cakes, putting them in the fridge can result in sweating. If you work VERY quickly once you take it out of the fridge, you should be able to get the edges sharp, while the fondant is still dry – but if you don’t, just put it straight back in the fridge to dry again.
Once you have finished your smoothing etc, bring your cake out of the fridge and let the sweat evaporate before you start decorating etc, or you’ll get paw prints all over it! If you leave the cake alone, it will dry out.
Anyway, I think I’ve covered everything, but the start find for me was the acetate, because I went from this level of sharpness only using fondant smoothers (which I thought was pretty good at the time):
to this level of sharpness using acetate:
I’m sure you’ll agree the acetate just makes it so much better!
Anyway, that was a long post – feel free to fire me questions and I hope this helped. :)