In Mexican tacos al pastor, the vertical spit used to roast the marinated pork is called a trompo.
The word trompo means “spinning top” in Spanish, describing the cone-shaped stack of pork as it rotates beside a heat source. Cooks shave thin pieces from the browned outside, usually placing them on small corn tortillas with onion, coriander, salsa, and pineapple.
Tacos al pastor developed in central Mexico from shawarma-style spit-roasting traditions brought by Lebanese immigrants in the early twentieth century. The dish became especially associated with Mexico City, where the pork is commonly marinated with dried chiles, spices, and achiote.
A trompo is not the same as a comal, which is a flat griddle, or a molcajete, which is a stone mortar and pestle. The vertical cooking method is the defining visual feature of this taco style.