Since we only have threads for recommending Aldi and Lidl stuff I thought I'd put this here: I had a yumnut from M&S (plain with icing, but they have other flavours) yesterday and they are absolutely delicious. Hands down the nicest doughnut type thing I've had in ages, way better than anything I've had in most of the doughnut shops that have popped up over the last years.
Mod Note:
This seems like a good beginning for a general supermarket thread