Heat the olive oil in a large 12-inch oven-safe skillet over medium-high heat. Add the chopped onion and cook for 4-5 minutes, stirring occasionally, until softened and translucent.

Add the ground beef to the skillet. Break it apart with a spoon and cook until fully browned, about 5-7 minutes. Drain off any excess grease.

Stir in the minced garlic, chili powder, cumin, smoked paprika, oregano, salt, and pepper. Cook for 1 minute more, stirring constantly, until the spices are fragrant.

Pour in the red enchilada sauce and stir in the rinsed black beans, diced green chiles (with their liquid), and corn. Bring the mixture to a gentle simmer and cook for 5 minutes, allowing the flavors to meld together.

Reduce the heat to low. Add the tortilla strips to the skillet and gently stir until they are coated in the sauce and distributed evenly. Let them cook for 2-3 minutes to soften slightly.

Sprinkle the 2 cups of shredded cheese evenly over the top of the skillet. Cover with a lid and let it cook on low for 5-7 minutes, or until the cheese is completely melted and bubbly.

For a golden, browned top, you can place the oven-safe skillet under your oven's broiler for 2-3 minutes. Watch it very closely to prevent burning.

Remove the skillet from the heat and let it rest for 5 minutes before serving. This allows the casserole to set slightly. Garnish with your favorite toppings like a dollop of sour cream, fresh cilantro, and sliced jalapeños.