I think some polenta sold here might be better described as mixed cornmeal tbh. It's useable but nothing like as good without a lot of 'helping' it out which might be why some people are having difficulty.
But when finances have been too tight to mention even the hard to make easily, has been an excellent staple.
You can make cakes, savory bakes, 'pizza,' crepes, bread all sorts with it.
Good polenta's made from 'otto file' or eight row flint corn. It's a particular deep gold strain of corn with eight rows of rounded, hard, flat kernels. The Italians in particular took to it and Italian food stores all over the place often sell loose polenta, how we get ours
I find Nigel's 20 min's cooking time a little scary, but maybe he's using finer more expensive grains or much lighter pots than we do?
What we get is cheap, low end of medium to coarse, ground. To make basic polenta we cook it low and slow in a covered pot stirred every 8-10 mins, for around 45mins, in either salted water, or sometimes Swiss vegetable bouillon stock, depending on what's being done with it after.
(NVN but as a non special 'ready meal' it can also be chucked into a slow cooker for 4 to 6 hours. If you can stir it every hour, so much the better, but as long as you don't mind a bit of clumping round the sides, you can get away with not being there to stir it. the clumped polenta can be pressed flat, layered with thin cheese slices, sprinkle with sage and a splash of oil, and chucked in the oven alongside whatever's in there, to make a nice cheese 'flatbread pizza' to accompany other things.)
It should be creamy and naturally slightly sweet. Adding cream and butter is traditional, but you can also instead use good herb olive oil, chilli oil, or truffle oil, and vegan elmlea, for Vegans, as well as Parmesan, Pecorino or goats cheese.(veggie versions for us) for Gluten free.