Essentially, costras are tortillas made of cheese that wrap around some kind of meat—perfect late-night food. Costra translates to scab, which isn't tempting, but it can also mean crust, which explains the texture of the cheese.

The difference between street tacos and regular tacos is that street tacos are smaller in size and made with a corn tortilla. Street tacos got their name from the place of their origin, the streets of Mexico. Mexican migrants that worked on mines and farms would wrap their tortillas around meat to eat on the go.