Wash and cut Daikon into 1/2 or 1/4 slices. Rub with 1/2 tsp. salt and leave for 20 min. Rinse and drain well.
In a saucepan, pour the pickled ingredients and boil it for several minutes. (This is to ensure the alcohol that contained in the Mirin will be evaporated.)
Combine all the ingredients in a Ziploc bag or container, and keep in the fridge overnight or a few days if you want a better taste.