Long ago, mustard plasters were thought to cure chest congestion and relieve arthritis, rheumatism, toothache, and soreness or stiffness. Today, many people commonly hold that a little mustard is quite good for digestion - but beware, large doses will cause vomiting. Mustard spread is made by crushing mustard seeds and adding seasonings and some kind of liquid, such as water, vinegar or beer. The sauce is simmered, then cooled. Sometimes, it is allowed to age before use.
Black seeds are more pungent than white seeds.
Grind together white and black mustard seeds. Add enough wine vinegar to mix it into a paste. Store it in a screw top jar. Mustard is at its most potent right after the seeds are crushed and mixed with liquid. If you like it hot, use it right away and store the remainder in your refrigerator to slow down the loss of pungency.