The word Vacio means empty, buy you could also take it as boneless. This cut is similar to a skirt steak and it comes from a loving grill that is always well stacked. A thing of pride in Argentina.
The sauce you see in the cover photo is the consistency of crushed watermelon, but it has a mean bite when sliding down your throat. It is some hot pepper from the south of the country, made by the owner.
Old world food at a family run restaurant.