In a skillet on medium heat, begin searing the ground beef and breaking it up well with a wooden spatula. Sprinkle in the salt and pepper, and let the meat sear well as you break it up.
When the meat is well-seared add in the onion and cook for 2 minutes, tossing frequently.Add in the chili powder, powdered garlic, cumin, and Mexican oregano and let the spices brown and toast in the pan along with the beef.
Finally, turn the heat down to medium and sprinkle in the flour. Toss the flour in the meat and incorporate into the fat and juices creating a roux of sorts. When the flour dissolves into the mixture, pour in the beef stock and whisk it into the mixture.
For the traditional pan method: Add 2 tablespoons oil to the bottom of a nonstick skillet and heat over low heat. Add a corn tortilla into the pan and fry for about 1-2 seconds on each side. Then transfer to a paper towel-lined plate for holding.
For the microwave method:Take all of the corn tortillas and wrap them in a damp paper towel. Place them on a microwave-safe plate and microwave for 45 seconds, the corn tortillas should be pliable enough to roll into enchiladas.