LAST week a restaurant opened in London entirely devoted to avocado. Reader, I was shocked.

Called the Avobar and based in trendy Covent Garden, its sole purpose is serving avocado in every which way you can think.

It started as a pop-up shop on the aptly-named Floral Street. Astonishingly, though, things went so well it managed to expand to its own restaurant.

That’s a proper restaurant. Full-time. Devoted to avocado, a fruit beloved of millennials and empty nesters. Avobar isn’t the first pop-up restaurant to hit the big time and move into its own premises.

More unusual, though, are pop-ups by existing restaurants and businesses. They’re mostly the preserve of celebrity chefs: sushi wizard Endo Kazutoshi at posh hotel The Berkeley or Helene Darroze at The Connaught.

Add to that list of famous names Helen Browning’s Chop House.

The Wood Street restaurant, which opened in 2016, embarked on its own pop-up experiment earlier this summer at The Tuppenny, Old Town.  

The bar on Devizes Road has no kitchen of its own, but a list of beers that would make a CAMRA committee wet themselves with delight.

Chop house chefs have kept the menu simple: burgers and hot dogs, mainly. It’s cooked fresh at the Wood Street chop house, before being whisked round in paper containers and served at your bar table. I was excited to try the food. I’ve eaten breakfast there before, but never dinner. I wanted to see if the burgers lived up to the hype.

I’d been drinking earlier in the evening. One of those accidental pub sessions, where you get talking to someone at the bar and before you know it you’re stumbling off a bar stool.

As a result, time moved a little quicker than it might otherwise have done.

The burger arrived within what felt like five minutes, but could have been anything from two to 20. It was a thing of beauty. Perfectly grilled bacon on top of a greasy, salty slab of cheddar and a glistening beef patty.

Helen Browning’s “thing” is organic food; and you can tell. The meat tastes like meat, not the ground boot leather you sometimes find in a takeaway.

Unlike a Big Mac – the king of burgers, as far as I’m concerned – there was no overpowering taste of mayonnaise or sauce. Just the earthiness from the beef and the tang of the cheese.

If anything let it down, it was the bun. When you’re eating food with your hands, you want something that’s capable of holding the patty. If your burger bun hasn’t been toasted, the chances of the meat patty slipping out and exploding over your trousers are increased tenfold.

Helen Browning’s buns were too soft; good at soaking up the juice from the meat, but less adept at trapping the meat into the burger.

But this was a good burger: tasty and tasty. It’s a burger for the festival-goer. Served in a paper box, eaten with your hands and with pints for £5 nine feet away, it felt like you could be at an upmarket countryside festival watching middle-class men waddle past in Hawaiian board shorts.

At around £10 depending upon the extras you heap on top, it’s not the cheapest burger you’ll find in Swindon. All you get for your money is the burger; no chips and a laudable lack of salad.

Verdict: worth it.