Preheat your oven to 350°F (175°C). This will ensure that your enchiladas bake evenly and get that delightful bubbly cheese top.
In a large skillet, heat 3 tablespoons of cooking oil over medium heat. Add the diced onion and cook until translucent, about 3-4 minutes. Then, add 1.5 pounds of lean ground beef to the skillet. Use a spatula to break it up as it cooks. Once the beef is browned, drain any excess fat.
Sprinkle the beef with 2 tablespoons of taco seasoning and mix well to combine. Cook for an additional 2-3 minutes until the spices are fragrant. Remove the skillet from heat and set aside.
In a separate skillet or in the microwave, warm the corn tortillas until they are pliable, about 30 seconds in the microwave or a few minutes in the skillet.
To assemble, spoon a generous amount of the beef mixture into the center of each tortilla, followed by a sprinkle of shredded cheddar cheese. Roll the tortilla tightly and place it seam-side down in a greased casserole dish.
Once all the tortillas are filled and arranged in the casserole dish, pour the red enchilada sauce over the top, ensuring all the enchiladas are covered. Sprinkle the remaining cheese on top.
Cover the casserole dish with aluminum foil and bake in the preheated oven for 20 minutes. Remove the foil and bake for an additional 10-15 minutes, or until the cheese is melted and bubbly.
Once baked, remove the enchiladas from the oven and let them cool for a few minutes. Garnish with freshly chopped cilantro and serve with pico de gallo on the side. Enjoy your Easy Ground Beef Enchiladas!