The gorgeous historic brick building, glittering glassware, shimmering chandeliers and vases overflowing with large blooms of flowers are reasons enough to visit this restaurant but I had another motivation; they have a new chef on board, Jono Beattie, and he's done time in the kitchens of dine by Peter Gordon and The Modern Pantry in London, so I was interested to see what treatment he's giving the food at Number 5.
On reading the menu it seemed "sensible" and easy to get your head around, but what emerged from the page to the plate was dazzlingly impressive. Chunks of lightly smoked snapper were served on an oyster creme, rich and deep with the taste of the sea and perked up with a fabulous tapioca crisp that cunningly replicated fish skin to look at and, texturally, was reminiscent of a prawn cracker.
From the woman who has eaten a lifetime of fresh oysters (my mother), the freshly shucked Oronga Bay beauties got the thumbs up for being "just briny enough", plump and fresh. We didn't hear a word from her as she happily slurped them down. My father and I ploughed our way through starters of a gorgeously unctuous and buttery liver parfait and rabbit rillettes with accompaniments that were each perfect. We loved it all and we'd only just begun - though we did find the staff slightly annoying.
The wine list at Number 5 is remarkable - well-maintained and crammed full of some of our most outstanding boutique wines, by the glass even, which are hard to pick up in New Zealand. For example we enjoyed glasses of 2009 Bridge Pa Reserve syrah, an award-winner which is almost impossible to find in wine shops. Exemplary.
A dish of duck was cooked two ways - a meltingly soft and moist confit leg and breast cooked rare. Duck is served all over town these days but what lifted this dish was the walnut pesto on top. Magnificent.
A lamb loin was cooked to perfection and for any overseas visitors, the best advertisement for this country I could think of.
Tuna rounds were served on a roasted aubergine puree with capers adding salt and asparagus stems - peeled I might add - added a taste of summer.
A rich, dark beef fillet sat alongside braised short rib on a musky mushroom puree with a darling roasted beetroot and potato gratin.
What you notice when dining at this level is that garnishes are well thought-out and vegetables are carefully considered and expertly prepared.
There were desserts, of course there were, but I don't have the room here to do them justice.
I will say, that the cheesecake - it is set, not baked, and is a triumph - was far better than the banana brulee which was one of the few clumsy notes in the evening.
We drifted out of Number 5 on cloud nine.
The next day I received impromptu calls from my fellow diners, each of them wistfully proclaiming that it was quite the best meal they'd had in a long time, recalling the flavours, the small touches, attentiveness of the staff, the magic.
It was everything dining out should be.