Creating your Cheesy Southwestern Ground Turkey Casserole is a straightforward process. Follow these steps to achieve a delicious result:

1. Preheat Oven: Preheat your oven to 350°F (175°C).
2. Cook Turkey: In a large skillet over medium heat, cook the ground turkey until browned. Break it apart with a spatula as it cooks, about 5-7 minutes.
3. Add Vegetables: Stir in the chopped onion and bell peppers. Cook until softened, around 3-4 minutes.
4. Mix Ingredients: Add the black beans, corn, diced tomatoes, cooked rice, chili powder, cumin, garlic powder, onion powder, salt, and pepper. Stir well to combine all ingredients.
5. Transfer to Baking Dish: Pour the mixture into a greased 9×13-inch baking dish, spreading it evenly.
6. Top with Cheese: Sprinkle the shredded cheddar cheese evenly on top of the mixture.
7. Bake: Place the casserole in the preheated oven and bake for 30-35 minutes, or until the cheese is melted and bubbly.
8. Garnish: Remove from the oven and let it cool for a few minutes. Garnish with fresh cilantro if desired.
9. Serve: Cut into squares and serve warm.

By following these steps, you will create a delicious, hearty casserole that embodies the flavors of the Southwest.