Place the flank steak on the grill at medium temperature and cook for about 20 minutes per side.
At the same time, to make the chimichurri sauce, blend the blueberries with a hand blender and set aside.
Dice the onion and garlic as finely as possible and mince the coriander.
Put all the ingredients together in a bowl and season with vinegar, chili paste, olive oil, some soy sauce to taste, lemon juice and oregano. Mix well and season with salt and pepper.
Cut the mushrooms into quarters and put in a pan over a grill or hot iron skillet with butter and soy sauce. Season with salt and pepper.
Once done, chop the flank steak into strips and serve with mushrooms and blueberry chimichurri sauce.
