For the No-Churn Chestnut Ice Cream could I substitute the rum with something non-alcoholic?
Nigella's No-Churn Chestnut Ice Cream (from NIGELLISSIMA) is made with sweetened chestnut puree (sometimes called chestnut spread), whipped cream, sugar and rum. The rum adds some extra flavour and also the alcohol helps to keep the texture of the ice cream slightly softer and more easy to scoop from the freezer.
You can omit the rum and we would suggest replacing it with 2 teaspoons of vanilla extract, or you could use a rum-flavoured essence (check it is alcohol-free, as brands vary). We also note that it is now possible to buy alcohol-free versions of rum. The ice cream without alcohol will be slightly firmer, so it may need to sit out of the freezer for 5-10 minutes (or about 30 minutes in the fridge) before it is scooped. If you can use alcohol but don't have any rum then bourbon, whisky or brandy could also be used.