In Sydney’s centre, on level one of The Castlereagh, a historic inner-city building owned by the City Tattersalls Club, chef Colin Fassnidge is turning out pub classics with just the right amount of retro. It’s a time capsule at the street entrance, an old-world gentleman’s club-meets-RSL vibe that would have many – and definitely the “hip and trendies”, as Fassnidge describes a certain clientele in his TV show Kitchen Nightmares – turn on their heels.

Fluorescent lights point into rooms and around corners to pokie machines; there’s a gym this way and a bar that way. But up the curved, marble-clad staircase it’s a different picture.

There’s a long bar fitted with taps featuring Kirin Ichiban, One Fifty Lashes and Stone & Wood, without forgetting VB. On the ceiling are hanging plants and the room is divided into smaller, cosy nooks.

At 11.30am, when The Castlereagh Bistro opens for lunch service, it’s “pension hour” and grey-haired duos order food and drinks at the bar, taking a number back to their tables with them. They’re sipping large glasses of chardonnay and living their best retired lives; gathering, laughing and pondering over that older-person favourite-slash-stereotype: meatloaf. It’s done here with a fried egg, split peas and gravy, and appears as two golden slabs with charred edges; light and fresh and yet comforting. Fassnidge’s take on the meatloaf is more like a revival than a rehash, a veritable bright young thing that balances recognisable-to-the-Club-crowd and modern.

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The crowd is mostly well-heeled retirees, who read the newspaper in actual paper form and drink a beer, delightfully in their element. But this is far from being the “old folk home” Fassnidge describes one kitchen nightmare on his hit show. The word has already spread – since the Fassnidge occupation in April this year – that there’s a damned good bistro within this unassuming destination. By the time the rest of the population usually eats lunch – between 12 and 2pm – the room is packed with a younger, professional, long-lunch crowd. The menu is touches of the classics from other Fassnidge restaurants Banksia Bistro, and before that Paddington’s Four in Hand and Surry Hills’ 4Fourteen. Fried zucchini flowers, a special from the blackboard, are on point – retaining a fresh bite, crispy batter, and stuffed with a beautiful herb-flecked goat’s curd. A generous portion of chicken wings is like an advertisement for juicy and crispy at once, and they sit in a puddle of spiced mayo that cuts pleasingly through the natural fattiness.

A Ranger Valley Black Onyx Tomahawk Steak is thickly sliced, appearing on a board beside the long bone, with chips and a light red wine jus. The food is brought to the table by cheery waiters who seem to know their clientele, mostly.

“They’re regulars,” our waiter explains, pointing to the table next to ours. She is comfortable with the old-school elements of the bistro, neglecting to bring side plates, or serving spoons for the spring vegetables, so we can actually share the share plates. We end up finding a pile of plates on a sideboard and help ourselves. It feels as though the new restaurant ways – fandangled ideas like share plates and hot celebrity chefs – have not yet completely rubbed out old-fashioned quirks, yet. Or maybe that adds to the charm of this place.

As we’ve witnessed on our televisions, there’s no doubt Fassnidge is up to the task of ironing out such bumps. The Club side of this enterprise supplies a captive, hungry audience, and Fassnidge’s menu is not failing to delight. This is top-notch, pub-style food, an idea previously missing in Sydney’s city centre. With Fassnidge’s bistro nous behind it, The Castlereagh has been delightfully transformed, bringing classics to a new audience without forgetting the old(er).

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