How Do You Work Out The Fan Oven Conversions?

Asked by LS1991. Answered on 16th May 2023

Full question

I had a problem with the oven temp advice for fan ovens for the Brownies recipe. Fan setting of 160c did not seem hot enough to bake these and I ended up with deceptive cooked-looking brownies only to get soup in the middle. I left these to cool and oven off so it was a complete and total waste. It is not the first time I have had problems with the fan settings suggested.

Brownies

By Nigella

Our answer

Nigella's recipe for Brownies (from [HOW TO BE A DOMESTIC GODDESS](/books/how-to-be-a-domestic goddess)) suggest baking the brownies at 180c or 160c fan. The time of 25 minutes is a guideline and as Nigella likes her brownies to be very squidgy, they will be quite soft in the centre. You do need to make sure that they are completely cold before you try and cut into them. The bownies will also become firmer if you refrigerate them. If you prefer a firmer, more cake-like brownie then you can bake for longer, until a cake tester inserted into the centre comes out with damp crumbs attached but not uncooked cake batter.

Nigella's recipes convert from regular oven temperatures to fan oven temperatures by reducing the temperature by 20 degrees celsius. This is a standard conversion that is used by most publications. We do test the majority of Nigella's cakes in a fan oven as well as a regular oven and we have found that the conversion works for our ovens. However, oven models do vary and some require different temperature adjustments for baking. We would suggest checking your oven handbook for advice as it may state a standard conversion, or some handbooks have a page with different conversions for different types of cooking (roasting, baking etc.).