Some very interesting suggestions here for “posh nosh” (or indeed even decent places to eat in Leeds!)
Leeds has some fine places to eat, but very very few could be considered posh.
Pool Court was fantastic, but it has long since gone (I worked with Geoff for a while, although not while at PC).
Anthony’s (while not a favourite of mine) was a good place to impress foodies, but again it closed fairly recently.
Moving away from posh nosh and into great food but not so posh surroundings, you have far more available. All have been mentioned previously, but I’d consider:
Kendells
Sous Le Nez
Harvey Nics 4th floor (surprised me on more than one occasion with great meals and wine, but have heard lots complaints from friends)
Foundry (added benefit of having Midnight Bell and Cross Keys (whose food is also excellent) nearby to finish your evening with great booze and a good crowd)
Gaucho if you want a nice big bit of meat
RBG is decent but i’d avoid at the weekend when service becomes slow and the noise drowns out all prospect of conversation unless you get a table out the back