Beef Birria is a popular dish that can be served as a soup or in a taco. Guajillo chilies are not hot and you can add your own level of heat to your serving with serrano chilies or hot pepper sauce. To make tacos, the tortilla is dipped into the broth, filled with meat, and fried on both sides to crisp it slightly. You can skim the fat from the birria and use it for frying. The taco is then dipped in the broth as you eat it.