TV

The Great British Bake Off
10x09 Pâtisserie Week
[Watch it (again) on All 4.]

The Great British Bake Off: An Extra Slice
6x09 Episode 9
[Watch it (again) on All 4.]

Jonathan Creek
5x00a The Grinning Man [Christmas special]
There was a five-year gap between the last series of Creek and this one-off special, which led to it doing big numbers in the ratings, and then more specials being commissioned. iPlayer and stuff like that list those specials as part of series 4, which is daft given that big gap; but they're also not part of series 5, which came several years later. Numbering systems for TV series aren't really built for shows that pop back and forth between one-offs and full series... Anyway, for now I'm going to number all those specials as "5x00" because I don't have a better answer.
[Watch it (again) on iPlayer.]

Lucifer
5x06 BlueBallz
5x07 Our Mojo
[Watch it (again) on Netflix.]

The Rookie
2x17 Control