Preheat the oven to 375°F (190°C).
Heat a large 12-inch oven-safe skillet or Dutch oven over medium heat. Add the ground beef, season with salt and pepper, and cook until browned, breaking it into small crumbles; transfer the cooked beef to a plate.
In the same skillet over medium heat, add the olive oil. When hot, whisk in the flour and cook, stirring, until golden, about 2 minutes.
Whisk in the chicken stock, tomato sauce, tomato paste, chili powder, cumin, onion powder, garlic powder, and smoked paprika. Bring to a simmer, season with a big pinch of salt and pepper, then reduce heat to low and cook 5 minutes. Taste and adjust seasoning as needed.
Add half of the torn tortilla pieces to the skillet with the sauce. Return the cooked ground beef to the pan, then add the frozen corn, diced green chiles, and a sprinkling of the grated cheese. Use tongs or a large spoon to mix until evenly distributed.
Top the mixture with the remaining tortilla pieces and then the remaining grated cheese in an even layer.
Transfer the skillet to the preheated oven and bake 20–25 minutes, until the cheese is melted and bubbly and the bake is heated through.
Remove from the oven and top with chopped tomatoes, sliced green onions, and fresh cilantro. Serve warm.