Ingredients are at the heart of cooking. Even the same ingredient can have infinite varieties, depending on where, which season, or under what weather condition they were produced.See more Wasan details
It's not a matter of simply cutting and cooking, but how to make the best use of the ingredients by finding the best way to cook them. For instance, tuna can be eaten as sashimi, steak or simmered in soy sauce. Making good use of ingredients means that we see the conditions of the tuna first and then choose the best cooking style.
Same goes for wine: even the producer is the same, the taste varies from each year of vintage, in which glass it is poured, or how long it has been aged. And sake can be dramatically different by the temperature it is served: hot, warm, or chilled.