Two northern Irish ones, both of quality but different ends of the scale in terms of audience.
Neptune and prawn in Portrush, very relaxed and we'll organised. Menu was a bit all over the place but the food was great. Can't book tables, first come first serve and you can wait in the cocktail bar upstairs which overlooks the harbour.
SAPHYRE, in Belfast, weirdly located in amongst student central in an old church. Really good food and service. The tasting menu was worth it. Definitely not cheap but I did think it was worthwhile.