In a saucepan, combine chicken breast with chicken broth, one quarter onion, a clove of garlic, and 2 teaspoons salt. Bring to a boil, and then boil for 20 minutes.
Set chicken aside to cool, and discard onion and garlic. When cool enough to handle, shred chicken with your hands.
Pour green chile enchilada sauce in a medium saucepan, and bring to a low boil.
Pour oil in a frying pan, and allow to get very hot. Slightly fry tortillas one by one in hot oil, setting each on a paper towel afterwards to soak some of the oil.
Finally, dip slightly fried tortillas in low-boiling green chile enchilada sauce for just a moment to cover.
After frying the tortillas and dipping in the green chile enchilada sauce, mix up the cooked shredded chicken with just enough sour cream to bind it, the onions, chopped green chiles, and 1 cup cheese.
Fill each tortilla with the chicken mixture, and a little green chile enchilada sauce. Roll them up, put them in 9X13 can, and cover with remaining green chile enchilada sauce and remaining 1 cup shredded mexican cheese,.
Bake in a 425 degree oven until cheese is melty (20 min?).
Top with crumbled/shredded cheese, chopped onion, and chopped cilantro and serve.