Mortars are also used in cooking to prepare wet or oily ingredients such as guacamole, hummus and pesto (which derives its name from the pestle pounding), as well as grinding spices into powder. The molcajete, a version used by pre-Hispanic Mesoamerican cultures including the Aztec and Maya, stretching back several thousand years, is made of basalt and is used widely in Mexican cooking. Other Native American nations use mortars carved into the bedrock to grind acorns and other nuts. Many such depressions can be found in their territories.