Gather the ingredients.

Combine chicken, broth, one quarter onion, salt, and 1 clove garlic in a medium saucepan; bring to a boil. Cook until chicken is no longer pink in the center and the juices run clear, about 20 minutes. An instant-read thermometer inserted into the center should read at least 165 degrees F (74 degrees C).

Remove chicken to a large bowl to cool. Reserve broth; discard onion and garlic.

When cool enough to handle, shred chicken with your hands.

Place tomatillos and serrano peppers in a medium pot and cover with water.

Bring to a boil and cook until tomatillos turn from bright green to dull, army green.

Strain tomatillos and peppers and place in a blender. Add remaining one quarter onion, remaining 1 clove garlic, and a pinch of salt. Pour in enough reserved broth to cover vegetables in the blender by about 1 inch.

Blend until completely puréed.

Pour salsa into a medium saucepan and bring to a low boil.

Heat oil in a small frying pan over medium-high heat until very hot. Lightly fry tortillas, one at time, in hot oil. Remove to paper towels to drain.

Dip tortillas in low-boiling salsa until they become soft again. Place onto plates, 3 per person.

Fill or cover tortillas with shredded chicken, then top with salsa.

Sprinkle with queso fresco, onion, and cilantro.