Ever wonder how your two pound burrito could possibly fit all of those ingredients without exploding? Well, that’s all thanks to masa, the corn flour used to make tortillas, sopas, and pupusas. While solid masa dough is traditionally sold in Mexican grocery stores in the refrigerator aisle, Bob’s Red Mill makes things easier by offering a nonperishable powdered version of the same stuff. In Spanish, masa harina literally translates to “dough flour”, and when mixed with water, transforms into a malleable dough that can be used in a variety of dishes.

How is masa harina made? What is it used for? To learn more about the science behind masa (which involves the process of nixtamalization) Kat interviews Dave Arnold, co-host of Cooking Issues. Masa and cornmeal are made from the sameprimary ingredient, but they are processed quite differently and have different outcomes when cooked. After corn is softened by lime water, some of the oil is broken down into emulsifying agents, and corn proteins are bonded to each other in the process. That's what makes it possible to form a dough from masa without introducing a bonding agent, such as the gluten in flour.

To get some tips about cooking sweet treats with masa harina, Kat visits Fany Gerson at the Flatiron location of Dough, her hand-made donut shop. Fany is one of the most authoritative voices on Mexican pastries and frozen desserts, and she shares a recipe for Tamal de Limón (Lime Zest Tamales) from her first book, My Sweet Mexico.