Cinnamon Tree

There are other trees also which decorate the hill, such as the golden lotus flower, the cinnamon tree, mālatī, kubja, mallikā and mādhavī.
(SB 4.6.16)

Regarding your first question, while Lord Jagannath is on His Ratha, and for the duration of the festivities for eight days following, bhuni kicrie may be offered along with other preparations. So for Rathayatra day feast should consist of bhuni kicrie which you make by first frying the dahl and rice in ghee. Also fry the vegetable with little ghee and massala. Then after the kicrie is cooked add some sugar, not enough to make it sweet, but just a little sweet taste, and some nutmeg, cinnamon, and other sweet spices. In this way it is like push pana. Other preparations may be a fruit salad, sweet rice, puries, a chutney, and a vegetable which is neither wet nor dry.
(700624 – Letter to Yamuna written from Los Angeles)