Thanks to a combination of its isolating mountains and fierce resistance, the Mexican state of Oaxaca escaped total conquest by the Spaniards in the 16th century. As such, Oaxacans have maintained a rich culture of indigenous traditions and dishes, including a frothy beverage called tejate.

A nutritious drink with subtle flavors of chocolate milk, tejate begins with a paste of toasted corn flour, cacao beans, ground-up pits of mamey (a honey-sweet fruit with bright orange flesh), and a white flower known as flor de cacao. Though the latter bears no relation to the cacao tree, it’s essential to creating tejate’s signature fragrant froth.

Vendors—traditionally women—knead a mixture of the paste and water in giant clay bowls. As they work, the ingredients release their oils, creating a thick, rich foam that rises to the surface as more water is added. The result is a light brown liquid capped with a layer of white foam that resembles a densely whipped cream.

As much a part of the average Oaxacan’s daily routine as a cup of coffee is in other parts of the world, a big serving of tejate runs about 15 pesos (or $1). Served over ice with optional sugar syrup, to-go tejate comes in a plastic cup with a straw, while to-stay versions are ladled into brightly painted bowls made of hollowed-out, dried gourds known as a jicaras. The slightly sweet drink, with its dense layer of foam floating at the top, is so nutrient-rich and high in fat, it’s filling enough to replace a meal—undoubtedly how the drink was consumed in ancient times.