For the Sauce:
In a stockpot, add the cleaned guajillo and ancho chiles along with 4 cups of water.
Cover and bring to a boil.
Turn heat off.
Let sit for 10 minutes.
To a blender, add all the chiles, 2 cups of water, garlic, onion, bouillon, oregano, cumin, and salt.
Strain the sauce into a separate container.
Gently push the sauce through the strainer with the back of a cooking spoon.
Set sauce aside until ready to use.
For the meat:
Separate the meat from the bone.
Salt and pepper the meat.
Heat the oil in a large stockpot.
Brown the meat, stirring occasionally.
Add flour to the meat pot.
Cook for 2 minutes, or until you can no longer see the white flour.
Add the sauce and remaining two cups of water.
Stir to combine.
Cover and cook on low-medium heat for 30 minutes.
Taste for salt.
Serve with rice, beans, and flour tortillas.