Below are photos of Hygrophorus hypothejus/ 'The Herald of the Winter'. It comes out after the first frosts of the year. It's a lovely mushroom, and richly coloured too.
I've never seen it before but it falls into the 'sticks out like a the sore thumb' category in my head. It's too distinct to be mistaken. I knew what is roughly was but not by name, just because I look through the books.
I confirmed it, but not like the descriptions or photos; the stipe had red flushes too.
The dark, slimy cap is interesting. It's made me wonder about its purpose.