10. Cassava (Yuca) Though not too widely used in the United States, cassava is a woody shrub that is generally found in the Caribbean and South America. When using cassava, it can either be made to be sweet or bitter. The taste, as well as the smell, all depends on the amount of cyanogenic glucosides, which are in fact, extremely poisonous. Most who prepare it like it to be bitter, as it keeps away insects and even animals. If cassava is prepared incorrectly, it can be deadly.... Full Story