British celebrity chef Heston Blumenthal is the king of presenting food as something it’s not – so it’s no wonder he endorses Fable, a startlingly realistic mock meat made mostly from shiitake mushrooms.

Since the Australian startup launched in 2019, Blumenthal has been using its products across several of his restaurants, including British fine diner The Fat Duck and Melbourne’s now-closed Dinner by Heston (where Fable had its launch party).

Now he’s taken that endorsement one step further, partnering with Melbourne-born burger empire Grill’d to offer four gourmet burgers made with the plant protein, including the limited-edition, “off-menu” Heston Fable Burger.

And by limited, we mean there are only 4000 burgers available from a select number of Grill’d outlets across the country, and if you want to get your lips around one, you even need to register your interest.

In typical Blumenthal fashion, it’s served with a side of theatrics. The signature Heston burger comes to your table under a smoke-filled cloche, with chips and white-miso mayo and paired with a glass of wine, beer or non-alcoholic beverage of your choice. The damage? It’s $35.

“No one’s ever done a burger collab with Heston,” Joshua Powell, head of menu innovation at Grill’d, tells Broadsheet. “This is a world first.”

It’s also the first time Fable has been used in this way. Fable has a texture and taste similar to beef brisket or pulled pork, but it’s completely plant-based. On supermarket shelves it’s sold in bite-sized pieces, but for this dish it’s been moulded into a patty that looks and tastes like beef.

It doesn’t “bleed” like some plant-based burgers, but the mouthfeel is eerily similar to a chewy piece of grilled steak, thanks to the mushrooms’ unique protein structure. The fun of Fable is that it doesn’t melt in your mouth but gives you something to work on – which, in my opinion, makes eating it all the more enjoyable.

Blumenthal says the Heston Fable Burger was inspired by Peking-duck pancakes, and is a remix of the burger he serves at The Perfectionists’ Cafe at Heathrow airport. It’s made by taking buttery brioche, adding a Fable patty and then topping with hoisin-marinated grilled tofu, slaw and crisp Fable crumbles.

“All four Fable burgers are fantastic, but the Heston Fable Burger is the star of the show,” Blumenthal says in a statement. “It has all of the umami, all of the satisfying things that you would expect from a burger, but there’s no meat in it.”

He’s right – it’s about as decadent as a meatless burger can get, though not exactly dainty. On first bite, I had sauce on my face and butter on my hands, but I’d argue it was worth the mess.

The other three burgers aren’t limited – anyone with $14.50 can get their hands on Blumenthal’s Fable Spicy Cheeseburger, Fable Truffle and Fable Southern BBQ.

The cheeseburger comes with aged cheddar, onion, mustard, pickles, mayonnaise and Heston’s fire-roasted spicy tomato sauce, while the truffle burger is dressed with aged cheddar, lettuce, basil and truffle mayo. The Southern BBQ comes with slaw, shredded carrot, onion, mayonnaise, pickles and Davidson’s plum barbeque sauce.

The three on-menu Grill’d Fable burgers are available for delivery and takeaway across Australia from Tuesday August 3. The limited-edition, off-menu Heston Fable Burger is only available at these Grill’d locations from Sunday August 8–22: Windsor, VIC; Hawthorn, VIC; Wintergarden, QLD; Carindale, QLD; Scarborough, WA. New South Wales residents can also register to experience the burger once dining restrictions ease. To reserve your seat, register here from Tuesday August 3.