In a large oven-safe skillet, heat a tablespoon of oil over medium heat. Add the lean ground beef and chopped onion, sautéing for about 8-10 minutes until the beef is browned and the onions are softened.

Once the beef is cooked, stir in taco seasoning and prepared salsa, mixing well. Then, add the black beans and sweet corn, along with the diced tomatoes and green chiles. Let the mixture simmer for about 5-6 minutes.

Reduce the heat to low, then add the cooked ready rice to the skillet. Stir until well combined, ensuring the rice is coated. Sprinkle shredded Colby Jack cheese over the top.

Preheat the broiler on your oven, and place the skillet under the broiler for about 1 minute until the cheese is bubbly and golden brown.

Remove the skillet from the oven. Garnish with fresh cilantro and other optional toppings. Serve hot.