Hi Nigella, first of all, I am a great fan of yours!. I wanted to ask what is the substitute of white wine in the Cheddar Cheese Risotto, as I cannot buy alcohol in my home state of Gujarat, India.
Nigella's Cheddar Cheese Risotto (from Nigella Express), like many risottos, uses white wine in the early stages for additional flavour. The wine is usually added first as the wine will reduce very substantially, meaning that most of the alcohol evaporates and leaves just the more subtle flavours of the wine.
However it is possible to use additional vegetable stock for the risotto, rather than wine. If you are able to get white wine vinegar then you can add a tablespoon of this to the rice and let it boil away before adding any stock and this will often give some of the flavour of wine, whilst reducing the alcohol content. However don't exceed 1 tablespoon of white wine vinegar as the acidity will be too high and don't try to substitute any other vinegars.
For those who may want to make the risotto and can use wine but don't have a bottle of wine open then you can use 3-4 tablespoons of dry white vermouth instead (a good storecupoard ingredient). Leftover wine freezes well for cooking so it is also worth stashing any leftover wine in the freezer to pull out on the day when you would like to make a risotto.