
Start by soaking the dried kombu kelp in water for about 20-30 minutes until it becomes soft. *3
Once softened, cut the kombu into small thin strips or small square shape.
In a saucepan, combine soy sauce, mirin, sake, and sugar. Bring the mixture to a gentle boil, stirring to dissolve the sugar.
Add the cut kombu pieces to the saucepan. Reduce the heat to low and let it simmer for about 20-30 minutes, or until the liquid has reduced and the kombu is tender and flavorful.
Add red chili flakes or sesame seeds for extra flavor and texture(Optional)
Allow the kombu tsukudani to cool slightly before serving. It can be stored in an airtight container in the refrigerator for up to a week.