Whether you’re after coffee in espresso or martini form, this welcoming joint shines a light from day to night. Sometimes the little gems are hiding in plain sight. Take the stretch of Flinders Lane – one-time garment district, now the Golden Mile of Melbourne restaurants – where the big ticket likes of Supernormal, Grill Americano and Kisume jostle for attention.

Just across the road from the Garden State Hotel, there’s the blink-and-you’ll-miss-it No. 100. Even the name (designating its location at 100 Flinders Lane) seems designed to deflect attention.

Opened a few months ago by founder of Code Black Coffee, Joseph Haddad, it’s understated in a calmly considered way. Out on the street, a few alcoves are set with candlelit tables for two (I’ll take mine in summer, thanks), while stepping inside is like immersing yourself in 1950s cosplay. A salumi case, espresso machine and deli counter bring all the lunchtime feels (take note of the cute booth, perfect for four to tete-a-tete their way through plates of prosciutto and salami, and maybe a sandwich bursting with chicken, stracciatella and rosemary-lemon mayonnaise).

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Cloistered behind screens of fluted glass, the compact dining room is another world entirely. Clever design includes a geometrically satisfying series of timber ceiling panels, presumably to squelch the sound while bringing a Mad Men vibe. There’s a gently undulating midnight blue banquette, timber wall panels and brass-girdled marble tables.

It’s easy to see why No. 100 has struck a chord with the post-work drinks crowd, who sit around happily kvetching about Gavin in HR over cocktails like the Laneway Aperitif (sage spiked fino sherry, dessert wine and tonic hitting an elegant note). The wine list is a cracker, too. A showcase of small-list smarts, it does less with more by prioritising the likes of petit Chablis, Albarino and Nebbiolo over the same-old sauv blanc and friends.

Chef Ryan Short is ticking a few boxes with a Euro-centric menu with some legitimate gems on board. Kingfish is done pastrami style, the firm flesh a brilliant foil to creme fraiche with pickled onions and a lick of chervil oil. There’s chicken liver pate, topped with a shattery disc of honey topped with a crumble of spiced shortcrust – what’s not to love? – and veal carpaccio giving the classic recipe a kick in the ribs with fermented chilli hollandaise, parmesan and fried capers. Squid “noodles”, too, subsumed into an ’nduja sauce, are a showcase of textured chilli heft.

From the trio of mains, pork belly is textbook stuff – sliced for easy sharing, it’s crackle capped, properly rendered and altogether delicious. Take points off for the ribbons of zucchini and x-ray thin green apple riding shotgun; barely dressed, they don’t make a lot of sense, particularly with winter howling outside. Nor does the salad we choose on the side – a bowl of shaved brussels sprouts with mint, walnut and the faint tang of seeded mustard that doesn’t supply enough acid backbone.

It’s a shame that an apple sauce that would have been great with the pork turns up on a slab of cheesecake. It’s good that the Basque classic hits all the right lactic tang, putty-textured notes. But I’m happy to shoulder the losses with the wins. Great staff, excellent drinks and some cracking dishes – plus that swoon-worthy room – add up to a place I’d like to linger longer. Perhaps not the full 100, but close enough.

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