My husband and I spent 2 weeks in Peru back in January, 1 of which was in Cusco. While none of the food in Peru majorly thrilled us (most was bland in our respectful opinion as we both like bold/intense flavors) our favorite place in Cusco was Uchu Peruvian Steakhouse. It was a neat and romantic spot where you could grill various types of meats at your table on a hot stone. Lots of options, moderately priced, good side choices, and a good cocktail/wine list if interested. A 2nd recommendation would be GreenPoint Vegan restaurant which was a neat semi-outdoor setting with all plant-based food, but the taste was so in that you couldn't tell!

Have a great trip.