01 - Preheat the oven to 375°F. Lightly grease a 9x13-inch baking dish.
02 - In a large skillet over medium heat, cook the ground beef until browned, breaking it up with a spatula for about 5 minutes. Drain excess fat if necessary.
03 - Add the diced onion and cook for 3 minutes until softened. Stir in the minced garlic and cook for 1 minute more.
04 - Sprinkle in the cumin, chili powder, smoked paprika, oregano, salt, and pepper. Stir to combine and cook for 1 minute.
05 - Pour in 1 cup of enchilada sauce and ¼ cup water. Simmer for 3 minutes, then remove from heat.
06 - Spread ¼ cup of the remaining enchilada sauce on the bottom of the baking dish.
07 - Layer 4 tortillas over the sauce, overlapping as needed. Top with half the beef mixture and 1 cup cheddar cheese.
08 - Repeat with remaining tortillas, beef mixture, and 1 cup cheddar. Pour all remaining enchilada sauce over the top. Sprinkle with Monterey Jack cheese, if using.
09 - Cover with foil and bake for 20 minutes.
10 - Remove foil and bake for an additional 10 minutes, until cheese is bubbly and golden.
11 - Let rest for 10 minutes before slicing. Garnish with cilantro, tomato, green onions, and serve with sour cream.