If it is fried mutton with green onions, marinate it with salt, light soy sauce, and cooking wine for 20 minutes, then stir-fry for a few minutes. If it is not marinated in advance, the large pieces of braised mutton will be cooked. It will take about an hour to get cooked, but depending on how you made it, the slices are just a little thicker, and you heated them in the microwave after frying, so they should be done.