Going back to the topic in hand . This is a great list of the best parillas in Buenos Aires . A good bife de chorizo or ojo de bife here can be world class and hard to beat elsewhere . I love mollejas and crave them at times . The best I have ever eaten were at el Mirasol in Recoleta and Don Julio in Palermo
https://www.tripadvisor.com.ar/Restaurants-g312741-c37-Buenos_Aires_Capital_Federal_District.html
Perry - if you haven't tried the mollejas at El Pobre Luis, give them a try. They are my favorite in Buenos Aires. Although, I have never eaten at Mirassol.