But in the nine short months since going off on his own again and opening the River Bistro, co-owner/chef O'Callaghan has started to win wider recognition. Already one of only three Limerick restaurants to grace Bridgestone's Top 100, the River Bistro has also been shortlisted as Munster's best restaurant by Food and Drink magazine. And it's not difficult to work out why.

As tempting as the black pudding salad with pear and raspberry (of which more anon) sounded, I decided to run with the rabbit for starters. Bugs, in the form of a pistachio-bejewelled sausage, was undeniably delicious but the main event in this dish – which came with mustard oil and leaves from Broadford, County Limerick – were the portobello mushrooms, which were musky perfection. Dunne's buttons are not for me and a mushroom has to be the size of a dinner plate to bring out its earthy goodness. This didn't disappoint. My fungus was humungous.

Terrine de foie gras with pickled mango and toasted brioche stayed my partner's conversation for a good 10 minutes. It was too good for words.

We left it to a table of British visitors to rhapsodise about the black pudding salad with pear puree and raspberry dressing – topped off with a poached free range egg.

Jacques Chirac and Silvio Berlusconi once vowed that they would never again attend an EU summit in Finland as the cuisine was so dreadful. I would have to agree with les seigneurs but the one good dish I had in Helsinki was the Finnish equivalent of black pudding served up with loganberries. Diarmuid said there was no Nordic inspiration behind this dish, just that they worked well together. And judging by our British diners' comments, it would have satisfied a voluptuary even as insatiable as Silvio.

Upon once ordering the endangered cod, my marine biologist sister shot me a look so withering it was as though I has ordered baby panda livers and corncrake. But the coast was clear this time to order it baked and topped with smoked salmon and crab meat, sweet potato puree on the side.

Pollock and hoki may be masquerading as cod at a Limerick chipper or supermarket near you but this was no cod, if you follow me – an absolute beauty and beast of a fish. Never has an Ahab-esque struggle with a monster of the deep been so rewarding.

I was further challenged by the slow progress my partner was making on her rib of beef. Lest it sound like a complaint, it too was despatched with relish. And restauranteurs who seem to be challenged when it comes to making chips, take note. Diarmuid O'Callaghan's actually taste like potato and don't flop about like a flaccid cheesestring. I have never had better in a Limerick restaurant.

Posset has been charming the sweet tooth since at least Renaissance times and was used by Lady MacBeth to drug Duncan's guards. I can't recall if Shakespeare's was a lemon posset, but it certainly didn't come with a raspberry sorbet and hazelnut shortbread.

My travails with the cod had left no room for dessert but I did sample the posset, which was tangy perfection.

With one lover of fish and one of flesh, we opted for the rose (I know, tut-tut). Chateau Rauzan Despagne is from Bordeaux but was just as satisfying as its more celebrated provencale cousins.

It is possible to eat this well is other restaurants in Limerick or in Adare but you can number these on the fingers of one hand. Crucially, you can expect to pay over €100 for dinner for two elsewhere. At the River Bistro, you get three courses, plus a glass of wine and coffee for €35 per head.

As befits a bistro, this 50-seat establishment is unfussy, in the best possible sense, in terms of the decor and the service, which was friendly and attentive. Long may this River flow.