BBQ Portobello Burger with Caramelised Onions & Saint Agur Cheese

By Martin Nordin
Viva
Martin Nordon's Portobello Mushroom Burger. Picture / Supplied

If you thought plant-based burgers were no match for their meaty counterparts, it’s time to think again.

Martin Nordin has amassed thousands of Instagram followers (@martin_nordin) with his photos of innovative vegetarian burgers, and now, his recipes have been compiled into a mouth-watering book. Suddenly there seems to be no excuse as to why some burger joints so often have one flavourless vegetarian option on the menu.

BBQ PORTOBELLO BURGER WITH CARAMELISED ONIONS AND SAINT AGUR CHEESE

Serves 6
Burgers

4 grilled and steamed spring onions

600g portobello mushrooms

Rapeseed or peanut oil, for frying

2 finely chopped garlic cloves

1 Tbsp butter

100g day-old sourdough bread, finely chopped

300ml BBQ sauce

2 eggs
Caramelised onions

2 onions

2 Tbsp butter

1 Tbsp red wine vinegar
To serve

120g Saint Agur, or another creamy blue cheese

6 burger buns Butter, for the buns

Finely chopped fresh chives, preferably garlic chives with flowers
  1. To grill and steam the spring onions, pour the oil into a ziplock bag big enough to accommodate the spring onions. Sprinkle with salt and pepper. Put the bag next to the barbecue so it is close at hand. Light the barbecue. Lay the spring onions on the grid while the charcoal is still actively flaming. Cook the onions all over so the surface gets a little burnt. Using tongs, transfer the spring onions to the ziplock bag. Seal the bag and shake it so the oil covers all the onions. Leave them in the bag for about 20 minutes so they steam.
  2. Cut the mushrooms into 5mm cubes. Heat the oil in a frying pan over a high heat until it starts to smoke. Add the mushrooms and fry them so that they take on colour – approximately 10–15 minutes.
  3. Chop the steamed spring onions and add them and the garlic to the mushrooms in the pan. Add the butter, reduce the heat to medium and cook for a few minutes, stirring.
  4. Remove the frying pan from the heat and allow it to cool a little. Then add the bread, BBQ sauce and eggs. Stir so that everything is well combined.
  5. Take a handful of mixture at a time and shape into 6 round patties, either by hand or using a food ring. Put the patties in the fridge for at least an hour, preferably longer, then they will hold together better when you fry them.
  6. Peel and chop the onions for the caramelised onion mix. Put the chopped onions and the butter into a cold saucepan. Cook over a medium heat and put the lid on. The onions will soon start to release liquid, and the flavours will be concentrated as a result of their cooking in their own juices. Stir with a wooden spoon about once every 5 minutes for 30–40 minutes, and check that they are not burning. (If you notice they’re starting to get too dry you can add the vinegar earlier.)
  7. Pour on the vinegar, increase the heat and cook for about 15 minutes, stirring, until considerably reduced. Put to one side.
  8. Preheat the oven to 180C using the grill function.
  9. Heat up a few tablespoons of oil in a frying pan over a medium heat. Fry the patties for a few minutes on both sides, until they develop a nice colour and a crispy surface. Transfer to an ovenproof dish and grill (broil) in the oven for 5–10 minutes.
  10. Put a little cheese on each patty and cook for a little longer in the oven, until the cheese has melted. This won’t take long, so keep an eye on them!
  11. Butter the buns on the cut surface and fry them quickly in a frying pan or grill them in the oven.
  12. Place a patty on the bottom of each bun. Splash on a heaped spoonful of the onion mix and top with chives.

• This is an edited extract from Green Burgers by Martin Nordin, published by Hardie Grant Books (RRP $33). Available in stores nationally.

Share this article:

Featured