Mustard seedMustard seeds are small, about 1mm in diameter. They may be coloured from yellowish white to black. They are important spices in many regional cuisines.
In the Indian subcontinent they are often used whole, and are quickly fried in oil until they pop to impart a flavour to the oil.
The seeds, particularly the white ones, can be ground into a flour, and mixed to a thick paste with a little water to make the condiment mustard. The ground mustard powder is usually mixed with ordinary flour to reduce the strength of the resulting condiment.
When initially mixed the sauce is mild in flavour, but it develops in time. Strong mustard has a very powerful (and painful) effect on the nasal membranes if eaten carelessly.
The whole seeds can be soaked in liquid before grinding to create whole grain mustard.
It is possible to buy ready prepared mustard in many places, but the freshly prepared product is usually far superior.