To caramelize the onions, heat a glug of Olive Oil with a generous knob of butter in a heavy-based saucepan and add the onions. Season with salt and the sugar to speed up the caramelization process. Fry, stirring occasionally, until softened and golden brown.

Combine the marinade ingredients in a large ziploc bag, add the tenderized steaks, seal well and squish it around to evenly coat the meat. Marinate overnight if possible, but 15 minutes will also do the trick.

Slice the rolls in half and place on a griddle pan or under a hot grill in the oven to warm. Lightly butter. Remove the steaks from the marinade, pat dry and lightly brush with Olive Oil so that they do not stick. Heat a heavy-based flat pan or griddle pan until smoking hot and sear the meat over high heat until nicely charred on one side before turning to cook the other side. Your steak should have a nice crust on the outside but still be pink in the middle. Only turn once otherwise the meat will not colour nicely.

Remove the steaks from the pan, place onto the prepared rolls to rest and season with salt.

Quickly add the remaining marinade to the same pan, and cook over high heat to reduce and heat the sauce. Pour over the steaks, top with caramelized onions, squash together with the other half of the roll and tuck in!