Cakes: What Each Step Does

Baking is less forgiving than cooking because each step does a particular job. Knowing what that job is makes it easy to see where a cake went wrong.

Weigh, do not measure

Scales are far more accurate than cups or spoons for flour and sugar. A cup of flour can weigh anything from 120 to 160 g depending on how it was scooped.

An easy pattern for butter sponges: weigh the eggs in their shells and use the same weight of butter, sugar and flour.

Room temperature

Take butter and eggs out of the fridge an hour ahead. Cold butter will not hold air when beaten, and cold eggs make a creamed mixture curdle.

Butter is soft enough when a finger presses into it easily without it being greasy or melting. Melted butter cannot be creamed at all.

Creaming

Beating butter and sugar together for several minutes, until pale and fluffy, is where a sponge's lightness comes from: the sugar crystals cut tiny air pockets into the butter, which the raising agent then enlarges in the oven.

If the mixture looks grainy or curdled after adding the eggs, add a spoonful of the flour with each egg. A curdled mixture still bakes, just a little more densely.

Folding

Once the flour goes in, the aim changes from adding air to keeping it. Fold with a large spoon or spatula, cutting down through the middle and turning the bowl, only until no dry flour shows.

Beating at this stage develops gluten and knocks the air out, which gives a tough, close cake with tunnels in it.

In the oven

Keep the door shut for the first two thirds of the baking time. Until the structure has set, a rush of cold air can make a cake sink in the middle.

A cake is done when it is golden, springs back when pressed lightly, is starting to come away from the sides, and a skewer in the middle comes out clean.

When it goes wrong

Sunk in the middle: underbaked, the door opened too soon, or too much raising agent. Domed and cracked: the oven too hot, so the outside set before the middle rose. Dense and heavy: cold ingredients, too little creaming, or overmixing after the flour went in. Dry: overbaked, or too much flour from measuring by volume.