If you are looking for something more fancy, but still in good price, you should visit MORENA restaurant. It is situated close to the main square in Cusco – Plaza de Armas and proposes in its menu many Peruvian dishes.
The staff is very nice, place is colorful and they take care of small details. Another very good thing is that the meals are served in good quantity, so you will not go out from this place.
Here you can check their website.