I came with a group of 6. We had a late lunch the first day we arrived in Cusco. It was so good, that we returned for an early dinner a couple days later. Both times, we were the only ones dining in the restaurant but we dined at off times. I would recommend making a reservation, as the restaurant is rather small.
It's on the second floor and overlooks Plaza de las Nazarenasv.
I recommend the Latin Ceviche which includes shrimp, octopus and fish. It may be small if you have a big appetite. But it was sufficient for me for a late lunch. I also recommend the Inkezuela Peruvian Beef with Spicy Chiles. It's a little bit like a stew. It's very tasty and hearty. The bread they give with the meal is great on it's own but also fantastic to dip in the stew.