Ingredients 
    
    - 14 day dry-aged bavette steak or skirt steak
 - 50 ml olive oil
 - 50 ml light soy sauce
 - 40 g soft brown sugar
 - 30 ml balsamic vinegar
 - 1 tbls. English mustard
 
Method
Note: This makes the base marinade, which tenderizes the meat with enough for up to 1kg of steak. This can be enhanced with a whole variety of flavours from crushed spices, fresh and dried herbs, garlic and onion powder or even a splash of Bourbon.
                    - Simply mix the ingredients together then pour into a zip lock bag, add the steak and marinade in a fridge, for minimum 2 hours or up to 12 hours.
 - Once marinated drain away excess juices and pat dry, bringing to room temperature precooking.
 
to cook:
- Preheat a griddle or heavy based frying pan large enough to hold the meat until it sizzles when you add a drop of oil.
 - Massage the steak with a little goose or duck fat.
 - Sear the steak on both sides over high heat creating a rich, dark crust then reduce to medium heat.
 - Cook 3 to 4 minutes each side basting the steak with foaming butter for the final couple of minutes of cooking.
 - For perfect skirt steak, press the steak with your thumb at the thickest point, it should have a slight spring to touch and a core temperature of 50°C before resting.
 - Leave to rest in a warm place for half the cooking time before carving into thin slices against the grain.