When writing recipes, I am actually uncomfortable about stating exact times a cake should be baked for. Even if you follow a recipe word for word, there are lots of variables which cannot be controlled. The size of your tin will determine the depth of your cake and, consequently, the baking time. Quite simply, a cake baked in a small deep tin will take longer to cook through than a cake baked in a shallow tin.
Then there is the oven. Not all ovens are created the same. Three people with there difference ovens set at 180c, for example, will find that their cakes will not be cooked by the same time!
I think it is more useful to treat baking times only as rough guides. Better to place your trust in your own powers of deduction to determine when your cake is ready.
There are several ways to test a cake to see if it’s done. But first, a word of caution. Don’t attempt any of these ‘test’ until at least two thirds of the recommended baking time has passed. In fact, you shouldn’t even open the oven door before this, as disturbances such as door banging, moving the cake tin, etc can cause a cake to collapse if the middle is still wobbly.
The Color Test: Many recipes tell you to bake your cake until it is golden brown, unless it is a chocolate cake with starts out dark anyway. If you cake has been baked at the right temperature, it should, technically, cook to a lovely brown color. But it takes more than color to indicate that a cake is done.
The Spring Test: if you touch the surface of the cake lightly with the tip of your finger, a cooked cake will feel spongy to the touch ad spring back. If it is uncooked, it will be soft and your finger may leave an indentation.
The Shrink Test: A cake shrinks slightly from the sides of the tin when it is cooked.
The Pick Test: if after the color, spring and shrink tests you are still not convinced that your cake is done, carefully insert a thin skewer in the centre of the cake – the part which usually takes the longest to cook. If you find sticky bit of better on it, your cake is obviously not cooked. A clean skewer or a few fine crumbs sticking to in indicates that the cake is done.
