Mustard vies with pepper as the world’s most important spice. The mustard plant bears its tiny seeds in a pod, much like beans or peas. The gray-green plants grow as tall as 10 feet, their bright yellow flowers dazzling in large fields given over to mustard. No one knows the origin of mustard, a plant spread by birds and wind across the Northern Hemisphere. It was cultivated early on, found in Stone Age settlements, and was the primary spice known to Europeans before the Asian spice trade heated up. Ancient people from India to Egypt to Rome munched mustard seeds with meat for instant seasoning.

The Romans most likely developed the prepared mustards we know today. They mixed grape juice, known as “must,” with ground seeds to form “mustum ardens,” or burning must. By the way, mustard powder alone has no sting—add liquid and it surges to life. From Roman times, France has been a mustard power. The city of Dijon has been its center since the 1200’s.

White mustard grows wild in North Africa, the Middle East and southern Europe and is cultivated as well in many places. Brown mustard is grown in the UK, Canada and the U.S., black, in Argentina, Chile, the U.S. and some European countries. Canada grows 90% of all the mustard seed on the international market.