The 3 secrets to icing a birthday cake easily

It may surprise you to know that I am not a baker. Literally, I never bake, except my kids’ birthday cakes.

In February 2020, my son turned one and I embarked on his first birthday cake with enthusiasm and ambition.

I grew up in the 80s, the era of “that train cake”, “that swimming pool cake” and “that Dolly Varden cake”. How fun was it going to be re-creating those cakes for my kid!

Not that fun, as it turned out. I had decided, in my infinite wisdom, to make my digger-obsessed son a digger-shaped cake. I searched high and low for cake tins that would make the shapes I needed, and when I couldn't find them I settled on a large, rectangular cake tin that I thought I would easily cut the cake shapes I wanted from. 

And I did manage to cut the shapes I wanted from my big, rectangular cake relatively easily. However, it was when I went to ice my cake with buttercream icing that I ran into trouble. The cake was a crumby mess.

Since that day, I have learnt many things about successful cake decorating. Here are my top tips. 

1. Get the consistency of the icing right.

The consistency of any buttercream icing recipe will vary depending on lots of factors - the quality of the butter you use, the temperature of the butter, the temperature of your kitchen being the main ones. So, whenever making icing, be prepared to adjust your quantities until your icing is the right consistency. 

How do you tell when icing is the right consistency? You use the spatula test: press a rubber spatula vertically down into your bowl of icing and pull it straight up, keeping the spatula in the vertical position. Then, flip the spatula so the rubber end is facing up and look at the icing that is on its tip. The icing should form a soft peak that has a little curl at the end - that curl is what you are looking for because it means the icing is stiff enough to hold up that curl, but soft enough to create the curl.

2. Start with the right shape cake or apply a crumb coat.

Cut sides of a cake will crumble considerably and those crumbs will mix into your icing. If possible, find cake tins that produce cakes that are the shape that you are after for your cake, so you don't have to cut and shape the cake yourself and can therefore avoid icing cut sides of the cake. If you do have to ice cut sides, or if your cake is very moist and has a crumby texture, apply a "crumb coat" (a very thin layer of icing) across the cut edge or any areas of the cake that are crumby first and let it dry. Then, apply a nice, thick layer of icing on top. The crumb coat will trap the crumbs on the cake and stop them from mixing into your second layer of icing. 

3. Heat up your tools.

I use a flat metal icing spatula to ice my cakes. Once the cake is covered in icing, I heat up the metal spatula using hot water, then dry it, then run the hot spatula over the cake to smooth the icing. This is like magic - the heat from the spatula instantly smooths the icing and creates a glossy, soft finish. 

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The 3 secrets to icing a birthday cake easily