Café de olla, literally pot coffee, is a traditional Mexican drink brewed in an unglazed earthenware pot with water, dark ground coffee, cinnamon, and panela, also called piloncillo, with orange peel, anise, and cloves as common additions. It is drunk mainly in cold climates and rural areas of Mexico, including high country in the Sierra Madre, alongside hearty staples like pozole, menudo, and tamales. The clay has high thermal mass and conducts heat poorly, so the pot absorbs the fire’s heat and radiates it back gently, holding a slow simmer instead of scalding the grounds.

Because the pot is unglazed inside, its pores absorb coffee oils and spice aromatics with every batch and release them later, seasoning it like a cast iron skillet, so an old pot brews differently than a new one. Piloncillo is unrefined cane sugar that keeps its molasses, bringing smoky caramel depth where refined white sugar would only add flat sweetness. Everything goes into the pot together from the start and simmers as one, placing café de olla in the family of simmered coffees with Turkish coffee from a cezve rather than espresso or pour over.

• Refined white sugar is about 99.9 percent sucrose; piloncillo is boiled cane juice poured into molds.
• Cinnamaldehyde in cinnamon and eugenol in cloves are vasodilators, which the episode sets against caffeine’s vasoconstriction.
• Piloncillo also delivers quick calories for early morning work in the cold.
• Long simmering pulls heavier lipids and oils that a paper filter would trap.
• Orange zest contributes limonene, and anise brings licorice-like anethole.