I would like to know if the semolina Nigella adds to her corn chowder in her Express series is known as polenta or maize meal (corn meal) in the UK. I'm finding it very difficult to find.
Semolina is made from wheat which is ground slightly more coarsely than it would be to make flour. Classically it is made from high protein durum wheat (the type used for making pasta) and is yellow in colour. It is often used for dusting baking sheets to prevent bread and cookies from sticking, it may also be used to dust fresh pasta or gnocci to prevent them from sticking too. It can be cooked into a type of porridge, often known as semolina pudding which was popular in the post-World War 2 era but is now rarely seen.
Its main function in the chowder recipe is to act as a thickener for the soup so you could use cornmeal or polenta as an alternative. It is worth checking in an Italian deli if you have one locally as they may stock it, and you can also buy semolina on-line in the UK from Nife Is Life (see link below).