Remove the stems and seeds from the chiles.
Cover the chiles with 4 cups of water in a stock pot. Bring to a boil. Immediately turn off heat and let sit for 5 minutes.
Discard the water.
Place the hydrated chiles in a blender along with 2 cups water. Blend until smooth. Strain the sauce.
To a large stock pot, add sauce and cinnamon stick.
Bring to a boil. Let simmer for 5 minutes.
Add salt, Mexican chocolate, and sugar. Stir to combine.
Cook only until chocolate has melted. Set aside.
Heat the oil.
Fry each tortilla for 2 minutes on each side.
Place tortilla on a paper towel to drain excess oil.
Dip the tortilla into the sauce and immediately put on a plate.
Add crumbled queso fresco. About 1 tablespoon.
Fold the other side over.
Repeat with all the tortillas until done.
Top with more queso fresco and sliced onions.