Prep the oven and pan: Preheat the oven to 375°F (190°C). Lightly grease a 9x13-inch baking dish with cooking spray or oil.
Cook the beef: Heat a large skillet over medium-high. Add a drizzle of oil, then the ground beef.
Season with a pinch of salt and pepper. Cook, breaking it up, until browned and no longer pink, about 6–8 minutes. Drain excess fat if needed.
Add aromatics: Reduce heat to medium.
Add the diced onion and cook until softened, 3–4 minutes. Stir in the garlic and cook 30 seconds until fragrant.
Season it up: Stir in chili powder, cumin, smoked paprika, and oregano. Add tomato paste and cook 1 minute to caramelize slightly.
Sauce the meat: Pour in 1 cup of enchilada sauce and the broth.
Stir to combine and simmer 2–3 minutes to thicken slightly. Taste and adjust salt and pepper. If using beans, corn, or green chiles, fold them in now.
Warm the tortillas (optional but helpful): Wrap the tortillas in a damp paper towel and microwave 30–45 seconds to make them more flexible.
This helps them absorb sauce evenly.
Layer 1: Spread a thin layer of enchilada sauce on the bottom of the baking dish. Arrange 4–5 tortillas to cover the base, tearing as needed for full coverage.
Add filling: Spoon half of the beef mixture over the tortillas. Sprinkle with one-third of the cheese blend.
Layer 2: Add another layer of tortillas.
Top with the remaining beef mixture and another third of the cheese.
Top layer: Add a final layer of tortillas. Pour the remaining enchilada sauce evenly over the top. Finish with the last third of the cheese.
Bake: Cover loosely with foil (tent it so it doesn’t touch the cheese).
Bake 15 minutes, then remove the foil and bake another 10–15 minutes until the cheese is bubbly and lightly golden at the edges.
Rest and garnish: Let the casserole rest 10 minutes so it sets for cleaner slices. Top with cilantro, green onions, or your favorite garnishes. Slice and serve with lime wedges and sour cream if you like.