Traditionally delicate pale colored river shrimp were used for this dish. As river shrimp are almost impossible to come by these days we used frozen shrimp. But let me quantify that statement. Frozen shrimp sold in Hong Kong is absolutely fresh when frozen and tastes pretty darn close to fresh shrimp. The Cantonese are famously picky about their shrimp. But as you know, once shrimp gets not fresh it just don't taste good at all.
Stir Fried Prawns with Longjing Tea (Longjing Shrimp for short) is a typical dish of Hangzhou cuisine. Just as its name implies, Longjing Shrimp is made by cooking peeled river prawns with tender shoots of famous Longjing tea.