Prep all ingredients: dice onion and bell pepper, mince garlic, drain and rinse beans, drain corn, and mix spices in a small bowl.
Heat a 12-inch cast iron or large skillet over medium-high heat for 1-2 minutes. Add olive oil and swirl to coat.
Add onion and cook for 2-3 minutes until translucent. Add bell pepper and cook 1-2 minutes until softening. Add garlic and cook 30-45 seconds until fragrant.
Push vegetables to the side, add ground beef, and break apart with a spoon. Cook for 6-8 minutes until fully browned. Drain excess grease if needed.
Add the pre-mixed spice blend over the browned meat and vegetables. Stir thoroughly and cook for 1 minute, stirring constantly, to bloom the spices.
Pour in diced tomatoes with their liquid, black beans, salsa, and corn. Stir everything together, scraping up any browned bits from the bottom of the pan.
Reduce heat to medium-low, cover, and simmer for 8-10 minutes until the mixture thickens to a saucy consistency. Taste and adjust seasoning.
Stir 1 cup of shredded cheese into the filling until melted and creamy. Sprinkle remaining 1/2 cup cheese over the top, cover, and let melt for 2-3 minutes.
Remove from heat, garnish with fresh cilantro and sliced green onions, and serve directly from the skillet with your favorite toppings.