Amish friendship bread is a type of bread or cake made from a sourdough starter that is often shared in a manner similar to a chain letter.
 The starter is a substitute for baking yeast and can be used to make many kinds of yeast-based breads, shared with friends, or frozen for future use.
 The sweet, cake-like Amish cinnamon bread is a common bread that is made from this starter; it is a simple, stirred quickbread that includes a substantial amount of sugar and vegetable oil, with a mild cinnamon flavor.
 It has characteristics of both pound cake and coffee cake.
 The flavor of the finished product can be altered by cinnamon being omitted.
Cinnamon leaf oil is obtained by steam distillation of cinnamon leaves and the oil yield ranges between 0.5% and 1.8%.
 More than 47 compounds have been identified from the leaf oil, the most significant being eugenol, which constitutes 65–92% .
 Cinnamon leaf oil is cheaper than bark oil and is used in the flavor industry, to a lesser extent, to flavor confectionary.
 It is also used as a source of eugenol for the preparation of synthetic vanillin.
 Cinnamon oleoresin obtained by solvent extraction is a dark brown extremely concentrated and viscous liquid, closely approximating the total spice flavour and containing 50% or more volatile oil.
 It is used mainly for flavouring food products such as cakes and confectionary.
 Ground spice has been replaced by oils and oleoresin in food industry.
Bukkumi (부꾸미 ) is a pan-fried "tteok" (rice cake) made with glutinous rice flour or sorghum flour.
 It is a flat half-moon shaped cake filled with white adzuki bean paste or mixture of toasted and ground sesame seeds, cinnamon powder, and honey.
 The color varies from white to yellow, pink, or dark green.
 "Bukkumi" is often coated with honey or syrup, and garnished with shredded chestnuts, jujube, or rock tripe.
Cinnamomum verum, called true cinnamon tree or Ceylon cinnamon tree is a small evergreen tree belonging to the family Lauraceae, native to Sri Lanka.
 Among other species, its inner bark is used to make cinnamon.
Cinnamomum cassia, called Chinese cassia or Chinese cinnamon, is an evergreen tree originating in southern China, and widely cultivated there and elsewhere in southern and eastern Asia (India, Indonesia, Laos, Malaysia, Taiwan, Thailand, and Vietnam).
 It is one of several species of "Cinnamomum" used primarily for their aromatic bark, which is used as a spice.
 In the United States, Chinese cassia is the most common type of cinnamon used.
 The buds are also used as a spice, especially in India, and were once used by the ancient Romans.
The Siege of the Portuguese fort "Santa Cruz de Gale" at Galle in 1640, took place during the Dutch–Portuguese and Sinhalese–Portuguese Wars.
 The Galle fort commanded 282 villages, which contained most fertile cinnamon lands in southern Sri Lanka It was also an important strategic coastal defense of Portuguese Ceylon.
 The Dutch, who were in an alliance with the Kingdom of Kandy, landed an expeditionary force under Commodore Willem Jacobszoon Coster of Akersloot, at the Bay of Galle, on 8 March 1640.
 After bombarding the fort for four consecutive days, Dutch troops stormed the fort and secured a victory on 13 March 1640.
 The Portuguese garrison, led by Captain Lourenço Ferreira de Brito, mounted a stiff resistance and unexpectedly high casualty rates among Dutch troops gave rise to the proverb “Gold in Malacca, lead in Galle”.
 With this victory the Dutch gained access to a large port which they later used as a convenient naval base to attack Goa and other South Indian Portuguese defenses.
 They also gained access to the Sri Lankan cinnamon trade and gained a permanent foothold on the island.
Cinnamon toothpicks are wooden toothpicks, round with one or two pointed ends, that have been soaked in oleoresin of cinnamon or cinnamon extract, then dried.
 Sometimes sweeteners and other flavoring ingredients are added.
 The wooden toothpicks used in America are typically cut from birch wood.
 Bamboo toothpicks are becoming increasingly popular due to its short growth cycle and carbon footprint reduction.
Cinnamon sugar is a mixture of ground cinnamon and granulated sugar used as a spice for desserts.
 It is commonly used to flavor foods such as Belgian waffles, Snickerdoodle cookies, churros and coffee cake.
 It is also found in breakfast cereals such as Cinnamon Toast Crunch.
Canella is a monospecific genus containing the species Canella winterana, a tree native to the Caribbean from the Florida Keys to Barbados.
 Its bark is used as a spice similar to cinnamon, giving rise to the common names "cinnamon bark", "wild cinnamon", and "white cinnamon".
Cider doughnuts are a harvest tradition in autumn in the northeastern United States and are sometimes sold at cider mills.
 They are often paired with apple cider, and may be covered with cinnamon and/or granulated sugar.
 They are "cake doughnuts" and get their flavor from cinnamon, nutmeg and apple cider used in the batter.

Question: Where does the cinnamon used in Bukkumi originate?
Answer: southern China