Heat a large skillet over medium heat. Add ground beef, diced onion, and minced garlic. Cook for 5 to 7 minutes until beef is browned and onion is soft. Drain excess fat.
Stir in chili powder, cumin, salt, and black pepper. Cook for an additional 1 to 2 minutes. Add tomato sauce and diced green chiles. Mix well and remove from heat.
Lay out flour tortillas. Spoon about 1/4 cup of beef mixture onto each tortilla. Sprinkle cheese on top. Roll tightly and place seam-side down in a greased baking dish.
Preheat oven to 350°F. Cover baking dish with foil and bake for 20 minutes. Remove foil and bake for an additional 10 minutes until cheese is melted and golden.
Let cool for a few minutes before serving.