The street is dark, there's no obvious sign, and the door is black. Is it a restaurant, a secret dive bar, or a locked office?

Aha! The door opens to reveal a dramatically red marble counter, lined with stools. Welcome to Restaurant Ka, a 10-seat degustation diner from a first-time chef-restaurateur.

If there's been one big trend in high-end dining in the 2020s, it's going small. Shrinking the space and the outlay on labour is a logical response to staff shortages, rising interest rates and escalating fit-out costs.

For now, it suits everyone. Restaurants get more control over overheads, and we get a more personal, charming dining experience.

Owner-chef Zachary Ng, who worked alongside Martin Benn at Sepia for 10 years, greets guests and seats them along the glossy marble bar. He takes orders for drinks and makes them himself ("I taught myself on YouTube" he says), then, when the full contingent arrives, welcomes everyone and sends out snacks.

In the kitchen, chef Benny Sanjaya of the sadly missed Cedric's Bistro and pastry chef Puspita Permata Dewi (Bennelong, Catalina), set out tiny pickled squid legs in a corset of seaweed, a buttery biscuit topped with grilled sweetcorn and a shower of grated manchego, and a little fried puff filled with foie gras. The latter is reminiscent of those adorable fried radish puffs at yum cha, only smaller. And better.

Working with local designer, Darren Kong of Studio Kong, Ng has made the place his own; moodily dark, with a back wall acting as an art installation of images of his own children. In spite of the glamour, the mood lighting and the gleaming kitchen, it's disarmingly modest (Ka means "home" in Cantonese).

The Cantonese touches on the menu swirl in and around Japanese influences as Ng's Hong Kong upbringing merges with his Sepia training.

A dish called "bigeye tuna spring roll" is a pile of shimmering tuna tartare and smoked salmon roe topped with horseradish cream, perched on a nest of crunchy fried slivers of spring roll wrapper.

Sourced from Narito Ishii of Wellstone Fish, the seafood is exceptional, and the techniques applied are mostly designed to keep it that way.

Port Lincoln calamari is skinned and sliced into long thin noodles, tossed in a hot pan for 15 seconds, and placed on a sauce of squid ink, spring onion and garlic, with burnt shallot dust in attendance. It's intense but light, fresh and sweetly sparkling.

Deconstruction strikes with a dish of prawn-turned-tagliatelle. New Caledonian Paradise prawns are crushed to a paste, rolled into sheets, steamed and sliced and served with a small stir-fry of mushrooms and broccoli. (Don't suppose you could just give us a prawn?)

The menu peaks naturally at the acknowledged "main" course, a burnished, lacquered Aylesbury/Pekin-cross duck breast, spice-rubbed, glazed with maltose and cherry brandy and dry-aged for two weeks before roasting and grilling. It's finely sliced, seriously delicious, and served with fat, juicy pickled cherries.

A fellow diner meticulously peels the skin from each slice and leaves it on the plate, and I nearly cry.

The concise wine list no longer has the 2019 Clarence House Block 1 pinot noir from Cambridge ($105) that I think will be the most duck-adjacent, but a rich and ripe 2018 Greystone organic pinot noir from Waipara in New Zealand ($100) steps up instead.

Timing-wise, they just squeak it in within the two-hour timeframe, making me think the number of courses could be dropped from eight to six and still give everyone a good time.

The charm is that in such a small space, there is no barrier between diner and kitchen.

It's fascinating to witness the professional precision and flow as the chefs assemble 10 simultaneous desserts of tea-poached peach, sable biscuit and a glossy cap of peach tea foam. The diner becomes part of the process; an insider, not just a consumer.

This going-small thing is so good, it can only get bigger.

The low-down

Drinks Bespoke cocktails, Chinese teas, boutique beers, French-led wine list, plus museum wines from Jon Osbeiston

Vibe Tiny hole-in-the-wall fine-diner that feels like a hidden secret

Go-to dish Aylesbury-Pekin duck, cherry and soy

Cost $180 for eight-course menu (wine pairing $100 a head)