Tonka beans
This flat, wrinkled legume from South America has been used for years in Latin American recipes and has become a fine-dining ingredient in recent years due to its impressive aroma with hints of vanilla, cherry, almond, and cinnamon.
But despite its worldwide appreciated flavor, the selling of tonka beans for human consumption has been banned in the US since 1954. The reason? Tonka beans contain a chemical compound called coumarin which has been found to cause liver failure when consumed in high doses.
