Sometimes my Forgotten Cookies come out too dry and crunchy - I'm trying to achieve perfect balance between soft and chewy inside but firm and crunchy outside. Apart from humidity and baking duration/time, are there any other factors that can affect this? I'm guessing the duration in the oven is the main issue - occasionally I've left them 10-12 hours. Thanks.
Nigella's Forgotten Cookies (from AT MY TABLE) are cookies that are put into a hot oven. The oven is then turned off and the cookies are left to cook in the cooling oven. It should give cookies with a crisp crust but a more marshmallowy centre.
A humid environment will make the cookies soft. Conversely, a very dry environment will cause them to dry out more, so if you live somewhere that is quite arid then this could cause the cookies to dry out more. We would generally consider 8 hours to be "overnight", so you could try removing the cookies from the oven after this time. After that, if you store the cookies in an airtight container for a day or two they should soften slightly, though the outside will not be as crisp either. It may also be possible to reduce the initial oven temperature slightly, to 170°C/150°C Fan/325°F if your oven runs slightly hot (you can check with an oven thermometer), but as we have not tried the cookies with this temperature we can't guarantee the results and would prefer to leave the cookies in the oven for a shorter period of time.