Warm the olive oil in a large oven-safe skillet over medium heat.
Soften the onion for 3–4 minutes, stirring occasionally.
Add the ground beef and cook until browned, breaking it up as it cooks. Drain excess fat if needed.
Stir in garlic, chili powder, cumin, smoked paprika, oregano, salt, pepper, and red pepper flakes. Toast 30 seconds.
Pour in enchilada sauce. Add black beans, corn, and green chiles. Simmer 3–4 minutes to meld flavors.
Fold in tortilla strips until coated and submerged in the sauce.
Scatter cheese over the top. Cover and cook on low until melted, 3–5 minutes.
Uncover, drizzle with lime juice, and sprinkle with cilantro. Adjust salt if needed.
Serve hot with a spoonful of sour cream and extra cilantro.