Cashews come from a tropical tree formally known as Anacardium occidentale.The tree produces a fleshy, pear-shaped stalk called a cashew apple on its branches.Instead, the true fruit is a smaller, kidney-shaped structure that grows underneath the cashew apple, also known as a drupe. Inside the fruit is where you find the edible seed that most people know as a cashew nut.The seed and its outer shell are technically considered both the nut and the fruit.