Birthday Cake - a postscript on scaling up

The more bling the better, when you are six!

Oh DL fans - the panic! Just starting to make a birthday cake for my not-so-little-anymore 6 year old DinnerBaby, and I decided that I should go BIG - we're off to the playcentre this afternoon and we need to supply the cake. Selfishly, I decided that I should make a much larger cake than my usual 8 inch round cake so that there would be enough left over for us as well, not just the vultures that are a gang of six-year girls!

Anyhow, this time last year I made a couple of 9 inch square cakes (as pictured in a previous post) so I reckoned that would be perfect. So off I went to get the notes from then, as of course I can't remember the details of scaling up the recipe that I worked out back then. Bear in mind that the party is at 3pm today and it is 11.30 at this stage, so you can imagine my panic when I can't find the notebook and remember how I threw it out recently.... Cue frantic searching and googling "scaled up cake recipes" and dodgy calculations with a pen and calculator trying to work out fractions of eggs, all the while screaming inside my head "I DON'T HAVE TIME FOR THIS!"

Sketchy note

Luckily, I found a dirty scrap of paper in my my Delia Smith book when I went to check my "master" cake recipe. Now, even by my standards, these details are on the sketchy side, so I thought I would record them for posterity here - and in case anyone else ever wants to scale up or down a recipe!

Just a note before I start - this is all in old "imperial" measurements. Mostly because that is what my Mum used for making cakes so it's "in my head" even though I use metric mostly for everything else. Also, these are basically the old recipes, which would all have been pounds, ounces and inches as well. Plus, it's so easy to remember 3-6-6-6 as the basic master cake recipe (as in, 3 eggs and 6oz each of sugar, flour and butter) that this is how I work it. Feel free to convert to metric if you are happier to work in grams.

The basic rule of thumb, according to Delia, is that if you have a round tin then you go an inch down, so my inverse of that means an inch up for a larger tin. My usual 3-6-6-6 cake is for 8' round tins, the square tins I have are 9' so I went with a scale up for 10' round - does that make sense?! I also cooked it at a slightly lower temperature and for about 3 mins longer than my smaller round cake. But now I've just tied my brain in a knot, so perhaps it would be easier for me just to give the recipe I used for the 9' square tins. As ever, all ingredients need to be at room temperature - you should be able to press the flat side of a knife through the butter with no effort.

The cake can look skimpy in the tin, don't worry

• 5 large eggs
• 10oz self-raising flour
• 10oz caster sugar
• 10oz soft butter
• 2 tsp baking powder
• 2 tsp  vanilla extract
• 2 tbsp milk
• 1 tbsp cocoa powder (if making a chocolate cake)
• Preheat the oven to 160C

1. As per normal, add the flour, eggs, sugar, butter and baking powder (and cocoa powder, if using) to a large bowl and just go in with the electric mixer - slowly at first as there is a lot of flour and you don't want it all to blow up in your face! Then increase the speed and mix for a minute or two
2. Add the vanilla and milk, mix again and the cake should now be a good "dropping" consistency, that is it should drop nicely off the spoon when given a sharp tap
3. Divide the mixture between your two tins, taking care to smooth the top out evenly. It does look like very little in the tin, but don't worry
4. Bake for 30 mins at 160C, it might need a couple of minutes longer as it is a bigger cake, but really no more than 3-5. It is done when the top is nice and springy to the touch and an inserted skewer comes out clean
5. Leave to cool in the tins for 5 mins before turning out onto wire racks to cool completely, before icing to your own - or rather, your 6 year old's own! - taste. We used pink buttercream for the middle, chocolate ganache on top (you'll find that recipe on the Boston Cream Pie post) studded with smarties and silver balls and then sprinkled with edible glitter and sugar sprinkles.... You'll find that bling, colour and sugar is what is most appealing to 6 year olds, not sophisticated good taste!

So, to summarise - I hope you were paying attention, class! If you usually use a round tin and want to make a square cake, your tin needs to be one inch smaller. If your square tin is bigger, then scale up  accordingly, so a square tin that measures one inch bigger will require plenty more ... I decided on two extra eggs and the corresponding amount of sugar, flour and butter. The tins are big though, so they would take more mixture if required; you'll probably need to cook them for longer though.

Give it a whirl - it worked for me, and you can probably tell I was flying by the seat of my pants! If you are considering scaling up or down a recipe, you can obviously already cook cake, so there is no need to worry, your judgement will see you through.

Sarah (on a sugar high, after a huge wodge of cake!)