Alkermes is a syrupy, spicy liqueur whose bright red color originally came from an unusual source: the scales of the kermes insect. In modern times, the bugs have largely been replaced with synthetic dyes (a few insect-tinted varieties remain), but the striking spirit remains a colorful and flavorful addition to Italian desserts.

Alkermes’s origins go back to ninth-century Persia, when a physician invented it as a nonalcoholic restorative. It was a drink for the wealthy classes, composed of spices and exotic ingredients such as gold leaf, crushed pearls, and ambergris, colored with kermes. In the 17th century, Europeans came across a similarly scarlet insect in the Americas. Known as cochineal, the species was easier to harvest and produced more dye. As such, it replaced kermes in the drink’s recipe.

In 1743, Dominican friars at the Santa Maria Novella pharmacy in Florence adapted the original Alkermes recipe, replacing the kermes with cochineal and the expensive ingredients with clove, nutmeg, and orange blossom. They promoted it as a potion to heal melancholy and weak hearts. The pharmacy was long supported by the noble Medici family, and when the liqueur was brought to France, it carried a new name: “Elixir of the Medici.”

Alkermes is still made in the Italian regions of Tuscany, Emilia-Romagna, the Veneto, and Sicily. It’s fairly alcoholic (20 to 35 percent) and may be sipped neat as an after-dinner drink. More commonly, wherever you see pink cakes in an Italian bakery—such as the dome-shaped zuccotto, the peach-shaped pesche dolci, or the sponge cake in the trifle known as zuppa inglese—you’ll know that Alkermes is its magic ingredient.