Andrew McConnell's ambitious new 150-seat cocktail bar and dining room, Gimlet at Cavendish House, was ready to launch in late March, days before COVID-19 hit the pause button. "The week before lockdown, we pulled the pin," McConnell says through gritted teeth. "It was such a difficult call, because we had assembled a crack team, front and back, ready to go."

The past three months have been a test of will and patience for McConnell, one of Melbourne's most prolific restaurateurs with eight venues and 300 staff around the city.

"The first two weeks I was in shock more than anything," he says. "There was a bit of anger as well. But once I got my head around that, I really focused on what we can do to fight this … it would have been disastrous if we'd opened [Gimlet] for a week and then closed, so in hindsight, it could have been worse."

The grand Gimlet, named after the cult cocktail of gin and sweetened citrus, will finally open its polished glass doors to 50 patrons from July 14.

McConnell gave Good Food the first official tour of the almost 400-square-metre venue, which occupies the ground floor of a late-1920s residential tower, Cavendish House, on the corner of Flinders Lane and Russell Street.

It's perched slightly above street level in the heart of the city's dining and fashion district, with Chanel across the road, and McConnell's all-day diners, Supernormal and Cumulus Inc. a stroll in either direction.

The 51-year-old chef remembers poking his head in when it was a contemporary furniture showroom called Dedece, and then a branch of electronics boutique Bang & Olufsen.

"Fifteen years ago I came through here and thought, 'My God, this would be cool as a dining space'," he says. "The soaring ceilings, columns, original windows, and the footprint is a perfect square. It was a dreamy palette to start with."

In May 2019, McConnell began the process by typing a mission statement into his MacBook. "The idea is to create an approachable space with a European sensibility and a bustling NY vibe," he wrote. "A bar that is reminiscent of a grand European diner, with intimate dining, a corner to hide in, or convivial space for a larger group celebration."

Caroline Choker and Vince Alafaci, of Sydney design firm ACME & Co, came on board to translate McConnell's brief for the vast space into a venue.

The duo designed Fred's in Sydney's Paddington, a similarly inviting and eclectic restaurant and bar, which served as an early inspiration. "The mood Caroline and Vince created [at Fred's] was so honest and wholesome and perfect," McConnell says. "It's not always about 'design, design, design': it's about lighting, acoustics, mood, how it makes you feel."

The result brings to mind big-ticket brasseries such as The Wolseley or Hoi Polloi in London or Balthazar in New York. "It's an ode to those big, old, grand European dining rooms we love so much when we go on holidays … when we used to go on holidays," he says.

There are plush circular booths under vaulted six-metre ceilings, with raised catwalks of seating along vast picture windows flooding in natural light. Many quirky vintage elements were sourced from Peninsula Antiques in Tyabb, lending a retro, one-of-a-kind vibe.

"I wanted it to feel quite timeless and I think in six to eight years it will start to look better and better with a bit of patina," McConnell explains. "I wanted materials to represent different zones: timber, leather and marble in the bar, then you step up into the dining room and it's carpets and linens, a little bit softer, a bit more gentle."

McConnell recalls a sneaky dinner he recently had here with his wife, Joanna, in the midst of lockdown. "One night we got takeaway from Tipo 00 and had date night in the empty restaurant … it was nice that we could have that indulgence."

With its chandeliers like massed tumblers by British designer Timothy Oulton, custom-upholstered Thonet chairs, and 1930s Murano glass lighting, it all looks very expensive, and understandably McConnell is keen to get patrons in the door.

At the centre of Gimlet is a sprawling, polished bar and at the back, an open kitchen, with a custom-made stainless steel, dual-chamber wood-fired oven powered by redgum blasting heat at up to 500C.

Head chef Allan Eccles (ex Cutler & Co) steps into the top kitchen role after launching Lesa, a sister restaurant to Embla, with Christian McCabe and Dave Verheul.

Bar manager Cameron Parish arrives after five years at The Everleigh, and long-time McConnell employees Christopher Handel and Shane Lazzo will manage the floor. Live music will also be a feature.

The lengthy menu, printed fresh each day, is made up almost entirely of new dishes, focusing on seasonal produce sourced from half-a-dozen organic farms around the state. When the kitchen wrote the first menu, it was summer, and ripe tomatoes figured heavily. Now it's evolved to be more winter-appropriate.

Guests will start with a snack at the bar – maybe an anchovy pastry, or something raw such as a sea urchin or an oyster – before moving to more substantial fare. They're experimenting with a seafood salad, a vegetable soup, a crab toast with finger lime. "I was thinking of having crumpets and pouring a bouillabaisse over it at the table," says McConnell, hinting at a new spin on his legendary lobster roll.

Starters might include a duck salad, or fresh mozzarella marinated in creme fraiche and showered with truffle. There'll be a perfect house salad, and perhaps a great burger or club sandwich at lunchtime.

"The food is European and I don't want to be pigeon-holed, but I like the simplicity and confidence of Italian cooking," continues McConnell. "I love the techniques of France and the flavours of Spain in summertime. I didn't want the menu to have a theme; it's about quality in the drinks and the produce and cherry-picking what we think is the best of Europe."

The backbone of the menu will be a selection of vegetable dishes cooked in that wood-fired oven. Treviso radicchio layered with guanciale and finished with a marjoram dressing, for example, or crisp potatoes splashed with taleggio cream. "I love cooking vegetables really quickly in a smoky wood-fired oven, it's just next level," McConnell says excitedly.

Meats will also be roasted over coals: a textbook pork cutlet, roast beef with tarragon, duck with Cumberland sauce and endives, a McConnell take on a seafood paella. Dessert might be scoops of impeccable gelato, a brown butter quince cake, or ripe cheese to finish. "The most important thing is that it's approachable. That's the key to what we're doing here," he says.

It will take some time before McConnell's master plan for Gimlet is fully realised. While he hopes it will be "two-deep at the bar on a Friday night" when rules allow, when it opens on July 14, numbers will initially be capped at 50 patrons, with one person per four square metres, including in a tucked-away private dining room designed for 12.

Before the official opening, the 30-strong team is warming up with a series of lunch and dinner preview events for 20 people. And when the doors open in a fortnight, they initially take bookings over walk-ins, although "no-shows" continue to be as much a problem now as they were before COVID. "It just hurts so much more now when we have restricted numbers," says the veteran restaurateur. "If we have one table who doesn't show up that's up to 20 per cent of the revenue for the night."

He won't consider doing prepaid or ticketed dining, or take deposits, or run everything via impersonal apps and tablets. "We want to be a spontaneous venue, and I don't want people to have to think about it too much," he says. "There are going to be things that are different [moving forward] but the core of our customers and what the industry provides won't change. Good old-fashioned hospitality … that doesn't need to change."

There are many unknowns around the future of hospitality, but his team is ready to tackle whatever lies ahead. They have every precaution in place: contactless produce deliveries, temperature checks and no handshakes at the door, plenty of sanitiser. And they're crossing their fingers.

Still, McConnell has been feeling increasingly confident these past few weeks after the low point of telling staff they could be out of a job (he found many of his overseas visa employees work on vintage in the Yarra Valley).

The JobKeeper program, due to end in September, has been a vital lifeline, and it will be "very difficult" trading at reduced capacity. "It's not all roses, and the industry as a whole is very concerned about what will happen in October," he says. "The industry is pretty much crippled, so an extension of JobKeeper will help."

McConnell has built his name on anticipating dining trends and delivering zeitgeist moments, often before anyone knows they want them.

And he has proven to be a savvy operator in difficult economic times: his flagship Cumulus Inc. opened in 2008 in the midst of the global financial crisis. "It was concerning at the time, but it made us think about where we sat in the market, our price points, accessibility, and that was our intent here [at Gimlet]," he says. "We'll be more price-sensitive because of the climate, but that's common sense."

McConnell admits opening a big new restaurant in a pandemic is terrifying. Gimlet is a big budget extravaganza worthy of any major city, and it will be hard to beat in terms of investment and vision for some time.

"It's not ideal, by any means," he says of the timing. "Even with a few runs on the board, it's no less risky, but in this environment it's even more nerve-racking … I've had many sleepless nights and I'm as nervous as I've ever been. But I think I've got a pretty good grip on what people like to eat, and also in the team around me."

Does Gimlet at Cavendish House have the goods to be the country's first post-pandemic hit? McConnell pauses for a long moment. "All I can do is hope we get it right, but you never know until you open the doors."