Step 1: Prepare the Ingredients

1. Preheat your oven to 375°F (190°C).
2. Dice the onion and bell pepper. Drain and rinse the black beans. Measure out all ingredients to ensure an organized cooking process.

Step 2: Cook the Ground Beef

1. In a large skillet, heat 2 tablespoons of olive oil over medium-high heat.
2. Add the diced onion and bell pepper, sautéing until they are soft and fragrant (about 3–4 minutes).
3. Add the ground beef, breaking it up with a wooden spoon. Cook until browned and fully cooked, about 5–7 minutes.
4. Sprinkle the taco seasoning over the beef mixture, stirring well to coat the meat. If the seasoning packet requires water, add as directed and let simmer for 2 minutes.

Step 3: Assemble the Casserole

1. In the same skillet, add the uncooked rice, diced tomatoes (with their juices), drained black beans, corn, and beef broth.
2. Stir well to combine. Let the mixture come to a simmer, stirring occasionally, for about 5 minutes until the rice begins to absorb the liquid.

Step 4: Bake the Casserole

1. Remove the skillet from heat and stir in 1 cup of shredded cheddar cheese and 1/2 cup of sour cream until well combined.
2. Transfer the mixture into a lightly greased 9×13-inch baking dish.
3. Top the casserole evenly with the remaining 1 cup of shredded cheddar cheese.
4. Cover the dish with aluminum foil and bake in the preheated oven for 25 minutes.

Step 5: Finish and Serve

1. After 25 minutes, remove the foil and bake for an additional 10 minutes or until the cheese is fully melted and bubbly.
2. Remove from the oven and let the casserole rest for 5 minutes before serving.
3. Garnish with freshly chopped cilantro and your choice of toppings. Serve hot and enjoy!