Creamy Mexican Casserole

Preheat the oven to 350 degrees F (175 degrees C).

Heat a large nonstick skillet over medium-high heat. Cook and stir ground beef in the hot skillet until browned and crumbly, 5 to 7 minutes. Drain and discard most of the grease. Add onion, garlic powder, cumin, chili powder, salt, and pepper to the beef and cook until onion is soft, about 5 more minutes. Remove from heat.

Mix condensed soup, milk, sour cream, and green chilies together in a large bowl until well blended. Add beef mixture and stir until incorporated. Transfer just enough beef mixture to cover the bottom of a 9x13-inch baking pan. Layer with 1/2 of the tortillas, 1/2 of the remaining beef mixture, and 1/2 of the shredded Mexican cheese. Repeat layers once more with remaining tortillas, beef mixture, and cheese.

Bake in the preheated oven until bubbly and cheese is melted, 30 to 45 minutes.