Porphyra rice balls such as sushi can be eaten cold without heating, but it is best to put some vinegar in the rice to help digestion.

You can pack anything you like in the rice ball, such as spicy radish, shredded eggs, all kinds of green non-leafy vegetables and pork floss. It tastes really good, and there is no soup, so don't worry about spilling it. It is also very simple, highly recommended!