01 - Set oven temperature to 375°F (190°C).
02 - Brown ground beef in a large skillet over medium heat. Add chopped onion and sauté until soft, about 3 minutes. Stir in garlic, cumin, chili powder, smoked paprika, oregano, salt, and pepper; cook for 1 minute until fragrant. Add diced tomatoes and simmer for 2 to 3 minutes. Remove from heat.
03 - In a saucepan over medium heat, whisk vegetable oil and flour constantly to form a roux, about 1 minute. Add chili powder, cumin, garlic powder, onion powder, oregano, and salt, stirring well. Gradually whisk in broth and tomato paste. Simmer for 5 minutes, stirring until slightly thickened. Adjust seasoning if needed.
04 - Lightly grease a 9x13-inch baking dish. Spread a thin layer of sauce evenly over the bottom.
05 - Warm tortillas until pliable by microwaving under a damp towel for 30 seconds or briefly heating on a skillet.
06 - Place 2 to 3 tablespoons of beef filling on each tortilla, add a small amount of shredded cheese, roll up, and position seam-side down in the prepared baking dish.
07 - Pour remaining sauce over rolled tortillas and sprinkle with the remaining cheese.
08 - Bake uncovered for 20 to 25 minutes, or until cheese is melted and bubbly.
09 - Garnish with chopped cilantro and serve with sour cream if desired.