From the 1600s to the 1800s, the sugar plum was a popular candy made of sugar rolled around a small ingredient in the center, such as a seed, nut, or spice. It may be surprising, but these treats had nothing to do with plums, the fruit, in a manufacturing sense, and got their name from their appearance rather than their flavor.

When making sugar plums, confectioners used a technique called panning, in which they poured liquid sugar repeatedly over a nut or seed center until a round, hard, thick candy shell formed around it. The treat would end up with around 30 layers of the smooth, glass-like shell, making it about the size and shape of a plum.

Due to the painstaking process of making them, in addition to the price of sugar a few centuries ago, sugar plums were not cheap, which built their reputation as a Christmas indulgence for lucky children. Panned confections like sugar plums also have an even longer history as medicinal digestives in medieval Arabia and Europe.