The Dutch blue poppy is considered the best. A member of the Papaveracea family, the poppy grows to about five feet tall with pink or purple flowers and produces seeds that are very small, kidney-shaped, and slate blue in color. It takes 900,000 of them to tip the scale's one-pound mark! While poppy seeds are difficult to grind, just dry roast them first and then you can stick them in your spice grinder or spice mill.
Not to be confused with their opium cousins (which are grown in Asia in particular in the "Golden Triangle" of Thailand, Burma and Laos), the culinary poppy plant is grown in Romania, Turkey, India, Australia, and the Netherlands (also known as Holland and home of the Dutch Blue). These seeds have a very low level of opiates compared to the seed pod and straw and are used only for cooking purposes.
The popular tiny seeds are liberally sprinkled on breads, pretzels, crackers and rolls, and they are delicious when mixed into cake, cookie or muffin batter and mixes or sprinkled on salads and noodles.
Some types of pastries are filled with a paste that is made from ground poppy seeds mixed with butter or milk and sugar.
In Austria, poppy seeds can be found on strudels and in Japan they are an essential ingredient in the popular spice blend Japanese 7 Spice. Northern Indian cooks sometimes grind the seed and use it to thicken sauces. In Greece, poppy seeds are mixed with sugar or honey to form candy bars. In many European countries, boiled poppy seeds are ground and eaten with different types of pasta.