For the Clementine Cake, can I cook the clementines ahead (e.g. cook them in the evening so they are ready for baking the next morning)?
Nigella's Clementine Cake (from HOW TO EAT) is a popular gluten-free cake. The clementines are cooked whole until soft, then drained, pureed (skin, pips and all) and used in the cake batter. The clementines do take a long time to cook as they have to be completely soft.
We suspect that it would be possible to cook the clementines a day ahead, but if they are being stored for more than a couple of hours then they need to be transferred to an airtight container and kept in the fridge. However it is very important that the clementines are brought back to room temperature before they are used. If they are too cold then the cake batter will not emulsify properly and the cake could become heavy or greasy. The whole clementines are likely to take an hour or so to come to room temperature, though it will depend on size. If you are in a hurry then you could roughly chop the refrigerated clementines, put them on a metal baking sheet and leave them in a warm place, as this will help them to come to room temperature much more quickly (approximately 20 minutes).