Wash peppers and set aside. Clean garlic cloves and chop the chadon beni. Using about 1 cup of vinegar blend the garlic and chadon beni. Pour out in a bowl and set aside.
Blend the peppers in 1 cup of vinegar. (Caution: use a spoon when handling the peppers).
Pour out the blended pepper into the bowl and add salt and mustard. Mix thoroughly. Place in a bottle and store in a cool place.