Because it is easy to prepare, using locally grown ingredients, this has been a popular dish in farming communities for centuries. To prepare the noodle broth, sesame seeds are ground in a mortar with miso, with a little sugar to taste. Chopped shiso (perilla) leaf, cucumber and ginger root are added to this mix. Diluted with some water or dashi stock, it makes a simple, tasty noodle broth, perfect as a refreshing midday meal in the summer months.