Ultimate Beef Enchiladas: Mouthwatering Homemade Sauce!

Heat vegetable oil in a saucepan over medium heat. Add flour; cook and stir using a wooden spoon until smooth, 1 to 2 minutes. Mix in chili powder and cook until fragrant, about 30 seconds. Stir in chicken stock, tomato paste, oregano, cumin, and salt; bring to a boil. Reduce heat and simmer enchilada sauce until thickened and smooth, about 15 minutes.

Preheat the oven to 375 degrees F (190 degrees C). Coat the inside of a 9×13-inch baking dish with cooking spray.

Heat a large skillet over medium-high heat. Cook and stir beef in the hot skillet until browned and crumbly, 5 to 7 minutes; drain and discard grease.

Heat olive oil in a separate skillet over medium heat; cook and stir onion, green chiles, and green bell pepper until softened, 5 to 10 minutes. Mix in ground beef and black beans. Stir in 1/2 of the enchilada sauce; cook and stir 1 to 2 minutes.

Spoon beef mixture evenly onto the center of each tortilla and roll tortilla around filling. Place tortillas, seam-side down, in the baking dish. Cover tortillas with remaining enchilada sauce and Mexican cheese blend.

Bake in the preheated oven until cheese is melted, about 20 minutes.