I like the recipe for Sesame Noodles from Nigella Express, but we have a person with nut allergies in our family. What could be used to replace the peanut butter so that they may be able to enjoy the recipe too?
Sunflower seeds are usually fine for nut allergy sufferers and if you can find it then sunflower seed butter would be a good alternative to the peanut butter. Sunflower seed butter can be found in some health food stores, supermarkets and also on-line (we have given some links below as examples, but other suppliers are also available).
Otherwise you could try using tahini (sesame seed paste). The flavour of tahini can be quite strong, particularly if it is combined with the oil and sesame seeds in the recipe, so we would suggest that rather than using the same quantity as for the peanut butter you instead add the tahini to taste. The first time you make the dish use a couple of tablespoons in the sauce then add extra to the noodles if you want more (mix the tahini with a little water to thin it before adding it to the noodles to help it combine more easily).
Sesame seeds are seen as quite a high allergy risk so we would suggest that to be safe you check with the person who has a nut allergy to make sure that they do not also have an allergy to sesame seeds (or even sunflower seeds).