Bar Margaux is a noisy, dusty worksite as chef Daniel Southern (The Craft & Co, Sth Central) and I convene around a small table for a preview of the bistro-style menu. Southern delivers a cheeseburger to the table, and the worksite behind us falls into the background. This burger demands attention.

The cheeseburger has its roots in 1920s America, but it’s not out of place in a French eatery, either. So too, Bar Margaux’s menu walks a fine line somewhere between a late-night New York diner and the brasseries of Paris.

Southern’s MGX Burger consists of two 120-gram Wagyu patties, bacon, organic sliced cheese, a 50-50 milk-brioche bun, and a classic bordelaise sauce made from bone marrow, red wine, shallots, and – in this case – a truckload of pepper. It’s a decadent experience; the bordelaise giving an oozy texture around the patties while a few other secret additions run liquidy riot through the rest of the burger.

“[It’s] French food, but also just good food,” says co-owner Michael Madrusan of the Margaux menu. “We’re not making a burger for people who are worried about what they eat. This is going to be a very indulgent burger. We guarantee that.”

Along with wife Zara (the couple also own Fitzroy cocktail bar The Everleigh and late-night city haunt Heartbreaker), Michael plans to open the doors to Margaux when the construction dust settles early next week.

Beyond the burger, the remainder of the menu continues to play comforting, liberal-with-the-butter-and-cheese cards, big on bold flavours and classic French techniques.

Escargot might not be common on Aussie plates, but those who love them know the dish is as much about the garlic and butter as the snails themselves. Here, they’re braised with garlic, salt and Pernod-spiked butter. Get the sauce on your fingers and you’ll be smelling garlic for days.

A golden cheese-topped bowl of soupe à l'oignon (French onion soup) is textbook in its approach but still shown a lot of care in preparation. It lands on the table covered in melted Gruyere with toasted baguette slices on the side. Dig your spoon through to find soup with hints of red wine, port and brandy in a beefy stock made with a base of five-hour caramelised onions.

A plate of duck frites (fries) looks deceptively simple and nowhere near as decadent as the parade of cream, cheese and bordelaise on the other dishes. But it’s equally debaucherous. Duck breast from Great Ocean Ducks is lightly cured, then slow-roasted, served pink in the middle and topped with a smooth, glossy duck sauce. Sliced and tender, you might consider eating it with your hands, running the duck and fries through the sauce in the process.

An ever-changing de jour menu offers beef bourguignon on Monday, bouillabaisse on Thursday and cassoulet on Saturday, among other traditional French fare. For dessert, there’s crème brûlée or a chocolate-mousse tart, or more fromage if you can handle it.

“We always knew if we were going to do food, it had to be food that we love,” says Michael. “And the food that we love in French cuisine is the simple stuff. We’re not looking for any awards. We’re looking to make people happy.”

A shorter supper menu runs from midnight until 3am on weeknights and 5am on weekends. The cheeseburger, onion soup and escargot will all be there, alongside steak frites, oysters, mussels and a special addition only for the post-12am crowd: croque monsieur with rotisserie lobster. The Madrusans both stress that they’ll be serving food right up until the end of the night. No early close for the kitchen staff, then.

I ask the couple, “Why so late?”

“It’s Melbourne, we’re allowed to do things late,” Zara replies, with a laugh.

Dinner menu, from 4pm

Hors d’oeuvres
Oysters
Steak tartare
Burrata, berries
Salade Lyonnaise, frisée, egg, lardons
Charcuterie
Soupe à l’oignon
Escargot de Bourgogne, garlic, Pernod butter
Pickled violet artichokes, smoked Meredith curd
Moules Marinières, Portarlington mussels, white wine, cream

La plat principal
Duck Frites (Great Ocean Ducks, Port Campbell)
MGX Burger, cheese, bacon, famous sauce, frites
Gnocchi Parisienne, Comté Gruyere, pickled onion, parsley
King George whiting fillets, Grenobloise sauce
Poulet roti (roasted Bannockburn chicken, Sutton Forest)
Bavette au Poivre, 280 grams (O’Connor, Gippsland)
Filet de Beouf, 220 grams (O’Connor, Gippsland)
Dry-aged sirloin on the bone, 600 grams (O’Connor, Gippsland)

Sauces
Béarnaise, Bordelaise, beurre persillé, poivre

Les garnitures
Salade verte
Sautéed spinach
Pomme purée
Haricot verts
Pomme frites

Supper menu, from midnight

La nuit
Oysters
Steak Tartare
Soupe à l’oignon
Escargot de Bourgogne, garlic, Pernod butter
Boudin blanc
Moules Marinières, Portarlington mussels, white wine, cream
MGX Burger, cheese, bacon, famous sauce, frites
Croque monsieur, rotisserie lobster, curry beurre fondue, Comté
Bavette au Poivre, 280 grams (O’Connor, Gippsland)

Les garnitures
Salade verte
Pomme purée
Pomme frites

Should I stay or should I gaux?
Crème brûlée
Tarte mousse au chocolat
Sorbet
Soufflé du jour
Fromage

Bar Margaux opens at the basement of 111 Lonsdale Street, Melbourne on July 1.

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