Prepare the Oven and Pan: Preheat your oven to 375°F (190°C). Lightly grease a 9x13 inch baking dish. Spread about 1/2 cup of enchilada sauce on the bottom of the dish to prevent sticking.
Cook the Beef: In a large skillet over medium-high heat, brown the ground beef with the diced onion. Cook until the meat is no longer pink and the onions are softened. Drain any excess grease.
Season: Add the minced garlic, chili powder, cumin, oregano, salt, and pepper. Stir in 1/2 cup of enchilada sauce and cook for another 2 minutes until everything is well incorporated and fragrant.
Assemble: Spoon a generous portion of the beef mixture onto each tortilla, top with a sprinkle of cheese, and roll tightly. Place the rolls seam-side down in your prepared baking dish.
Smother and Bake: Pour the remaining enchilada sauce evenly over the top of the rolled tortillas. Sprinkle the rest of the cheese over the top.
Bake: Cover the dish with foil and bake for 20 minutes. Remove the foil and bake for another 5–10 minutes, or until the cheese is bubbling and slightly golden.