Preheat the oven to 200C. Season steak on both sides with salt and pepper.
Mix the chimichurri ingredients in a bowl & set aside.
In a pan on high heat, heat some olive oil, add your steak and cook for 2 minutes either side.
Once cooked, add to the oven for 6-7 minutes for medium rare. Remove from oven and allow to rest for 10 minutes.
To the same pan over medium heat, add the sliced onions with a pinch of salt and sweat down. Once they’re almost cooked, add the honey and caramalise for a further minute.
Now it’s time to assemble, add the mayo to the burgen soy & linseed bread, top with lettuce, tomato, sliced steak, cheese, onions, chimichurri sauce, top with bread, slice & enjoy.