in no particular order
This website includes some of the best restaurants in Cusco, all recommended http://www.cuscorestaurants.com/
Support social projects while eating. New, worthwhile venture!
Fallen Angel (Plaza Nazarenas) – for its food as well as its innovative decor
Ciccolina (Triunfo) – often considered the best in Cusco.
Limo Cocina Peruana & Pisco Bar
Considered one of the best restaurants in Cusco. Specialize in seafoods and ceviches.
Chi Cha – Gaston Acurio´s new restaurant in Cusco.
La Chomba specializes in traditional Cusconian food http://www.tripadvisor.es/Restaurant_Review-g294314-d2218612-Reviews-La_Chomba-Cusco.html
Baco’s – (Santa Catalina)
Korma Sutra – Tandapata – Cusco´s best curries.
Jack´s Café – a Cusco institution – great for breakfast or anytime. Usually need to wait.