Fan-forced oven setting

Q: I don’t completely understand how the fan-forced setting on my oven works. Can you explain please?

A: When you use the fan-forced setting, the fan in the back wall of the oven evenly distributes the heat from the element that surrounds it. This means that, if this setting works efficiently in your oven, there is no need to swap or move trays of biscuits or cake layers around during the cooking process to ensure even cooking and browning, as you would if using the conventional setting.

If you are using the fan-forced setting, you will need remember to make minor adjustments to the temperature and/or cooking time. The reason for this is that the fan means that the oven works more efficiently – because the air in the oven is being circulated by the fan the temperature isn’t any higher, it’s just more intense and bakes more quickly. You therefore will either have to bake for less time or drop the temperature of the oven slightly. As a rule of thumb, I find that dropping the temperature by 20°C (for example, if the recipe specifies to preheat the oven to 180°C you will need to set the temperature to 160°C fan-forced) is the easiest adjustment to make to allow for the more intense heat. I’ll then bake for the recommended time, checking it 5 minutes before the end of baking. Make sure you note these adjustments on your recipe for next time.

Also, it is interesting to note, that because the oven temp isn't hotter, just more intense, if you have a portable oven thermometer inside the oven it will still only register the temperature the oven is set on. For example, the thermometer will register 160°C if the oven is set on 160°C fan-forced.