Baking and Ratios

A love of maths is a supremely helpful quality for baking. Even if I mostly divide recipes by use of chrome’s toolbar rather than in my head these days, it’s my good old standard grade maths grounding that means I know to type in “300/3*2” to work out that 2/3 of 300 is 200. Ok, so I wouldn’t actually have to type that in to work out that particular sum. Honest. Apparently you’re not really meant to tweak recipes which specify a number of eggs, but I’ve never had any problems with doing so: if you don’t have a large enough baking tin or enough people to feed to do the whole batch of 20 brownies, I’ve found doing 2/3 of it in a smaller tin works perfectly.

Anyway, so one of the great things about baking is ratios. Though I’ve known for years that the basic sponge cake recipe has the perfect ratio of 1:1:1:1 for the weights of butter:sugar:eggs:self-raising flour (cream butter and sugar; beat in eggs 1 at a time; fold in half the flour then the other half then bake for about 20 minutes at gas mark 5*), and discovered recently that 1:1 for cream:chocolate makes the perfect ganache (or truffles), for some reason I’d not really thought of extending that to other recipes. But actually, it makes them so much easier to remember. And when I was given a recipe for

Chocolate Truffle Cake

By the lovely Sarah W, it was the perfect opportunity to test this ratio thing out further.

(apologies for photo quality, my camera was elsewhere so had to use a blackberry. Also, in the words of someone that wasn’t me: “It looks ok but tastes amazing!”)

The basic recipe serves about 8-12 depending on your portion-size, costs about £3.50 depending on the quality of your chocolate, and is:

225g digestive biscuits

450g dark chocolate

100g butter

1 pt double cream

cocoa powder/grated chocolate (for dusting/decoration).

1. Relieve all your stress by bashing the digestives repeatedly over the head with a rolling pin until they are completely smooshed (my interpretation of  “smash biscuits to rough crumb form”) and melt the butter.
2. Mix the crumbs and butter and press into a spring form cake tin (around 24cm). Place in the fridge.
3. Melt the chocolate carefully, either in a bowl on top of some boiling water, or on a really gentle heat on the stovetop directly in a pot, or by turning the microwave power to low and stirring frequently.
4. Whip the double cream until stiff.
5. Pour in the melted chocolate and fold in gently – this may take a little time, but keep gently folding, making sure you don’t overmix.
6. Pour chocolate cream mixture in over the base and leave to set in the fridge overnight.
7. Dust with cocoa powder before serving.

But if you know that a pint is roughly 550 ml and it’s a sort of basic ganache topping (though the difference in method means it comes out completely differently), then you can take that ratio and make it 2:1:4:4 in terms of digestives:butter:chocolate:cream. And then make it for as many or as few people as you want. I had only 400g of chocolate so did 200g:100g:400g:400ml and that worked out fine (I also substituted the dark chocolate for 3 bars milk and 1 bar dark, and the double cream for single as the shop had run out, and that worked well – its recipients raved [somewhat to my surprise, in fact!], but I think it would be even better made with double or whipping cream as directed).

End summary: have fun, experiment, and look to see if your favourite recipes have an innate ratio that make them much easier to remember. And stay in school, kids, maths is the key to success…

*Interestingly when procrastinating by investigating for doing this blog, I found that using this method with plain flour should yield the denser pound cake. While for a different type of sponge cake, you can reclassify the ratio as egg:sugar:flour:melted butter (whisk eggs and sugar, fold in flour [plain or self raising], fold in melted butter)