For a superbly gluttonous experience visit Cabana Las Lilas in Puerto Moderno. This popular, busy, touristy and well respected establishment is pricey, but good. The evening starts the minute you're seated with aperitif and tapas. Las Lilas is best known for its beef, from which there are many cuts to choose. The salad selections, side veggies, fries and rice options are great as well. As a digestif, the table is brought limoncello following the meal, as if you hadn't had enough already. Before calling it a night, I'd suggest taking the time to walk off dinner along the promenade by the river outside.
The top steak restaurant in the restored Puerto Madero docklands, Cabaña Las Lilas occupies a lovely old red-brick warehouse with wood floors and exposed cast-iron struts and columns. The house gets its beef—Angus, Hereford, Brahman and more—from its very own estancias, and the wine list is as ample as you’ll find anywhere.