A molcajete is a mortar, a rounded container which is designed to be used with a pestle to grind food ingredients. Molcajete is a Mexican Spanish word; it is typically paired with a tejolote, or “pestle.” A molcajete y tejolote is required for the production of a lot of traditional Mexican dishes, including salsa and guacamole, and this kitchen tool can be useful for cuisines from other regions of the world as well. Many Mexican markets sell molcajetes and tejolotes, and you can also order them from artisan producers in Mexico.
Archaeological evidence suggests that the molcajete was developed around 4,000 BCE, and possibly even before then. This early kitchen utensil was probably related to the metate, a stone grinder which is even older. Molcajetes were used by early Americans to grind herbs and spices, prepare pureed foods, and to crush corn and other grains. Remains of these ancient meals can be seen at some archaeological sites, providing evidence about what Mesoamericans ate.
A traditional molcajete is made from basalt or lava. These rocks are very coarse and porous, allowing them to grind food and acquire a seasoning over the course of years of use. It is also possible to find mortar and pestle sets made with wood, marble, pottery, and other forms of stone; although not traditional, some of these sets are perfectly adequate, although a traditional basalt molcajete will endure multiple generations of use.
Before a molcajete can be used, it must be seasoned to remove grit. Many people start by soaking the molcajete in water and allowing it to dry completely, removing surface dust. Then, a grain such as corn or white rice is ground in the molcajete. As the grain is ground, it will turn gray, a result of the residual grit in the mortar. After several changes of fresh grain, the grain should remain pure white, at which point the molcajete can be rubbed with a mixture of herbs and then used.
Using a molcajete is fairly simple. The food which is being ground is piled into the molcajete, and the tejolote is moved in an up and down motion to grind it. You may find that starting with a small amount of food works best, establishing a base to which you can add more food. As you pound the food, it will release volatile aromatic compounds, becoming flavorful and quite strongly scented, which is exactly how you want it, whether you are using it as a seasoning based for a cooked dish or sprinkling it on top of a finished product.
