Masa harina noun

Flour made from corn that has been cooked in lime water (nixtamalised), dried and ground; the flour of tortillas and tamales.

Toasty, sweet corn with the distinct lime-treated (nixtamal) aroma that ordinary cornflour lacks.

Mix with warm water and a pinch of salt to a soft dough, rest, press into tortillas and cook on a dry comal; thicken soups and stews (atole, pozole); make tamales with lard and stock. Cornflour and polenta will not work.

Nixtamalisation is a Mesoamerican technique thousands of years old that unlocks the corn's niacin and gives masa its pliability. Masa harina made the process available to every kitchen in the twentieth century.