Mix all ingredients together in a bowl and taste a little to see if the balance of flavours is right. Keep at room temperature and serve the same day. Typically, make in the morning to serve with roast beef for lunch. Also wonderful on grilled steak or salmon.
Horseradish must be used fresh, and is seriously pungent. Preserved horseradish out of a jar is to fresh horseradish as Tabasco sauce is to fresh habanero.