My Spanish Chicken With Chorizo and Potatoes was burned and I followed the recipe to the letter. I did make adjustments to the temperature as I used a fan oven. Next time I used the convection oven, with the same results. All other recipes are fine in my oven.
Nigella's Spanish Chicken With Chorizo And Potatoes is traybake where the meat and vegetables are roasted together. It is cooked at a fairly high temperature to encourage the ingredients to cook until crisp. A convection oven circulates heat around the oven in a similar way to a fan oven, so the cooking time and temperature may still need to be adjusted. Sometimes with a fan or convection oven the cooking time will be slightly shorter, even if the temperature is reduced, so it is worth checking after 45 minutes. It is also a good idea to roatate the pans halfway through cooking, even in a fan oven. If the ingredients are quite spread out then they will cook more quickly so it can help to try and nestle them together in the roasting pan.
If you are using a baking sheet that has has a shallow lip then the ingredients may also cook more quickly so we would also suggest checking after 45 minutes. Nigella uses a shallow roasting tin or a US-style half sheet pan that has a depth of at least 2.5cm (1 inch). If possible, try to find a pan where the skin of the chicken rises just above the sides of the pan, but the remaining ingredients sit inside the pan.