炒菜 is a noun that refers both to a stir-fried dish (the result) and to the cooking method of stir-frying (the process). As a noun, it can be used like any other dish name: 点一个炒菜 ('order a stir-fry'). It can also appear in contexts like 炒菜比炖菜快 ('stir-frying is faster than stewing'), where it names the technique. The verb form 炒菜 ('to stir-fry dishes') is a separate usage not covered by this noun entry.