Heat a large oven-safe skillet over medium heat. Spray with oil, add ground beef and diced onion. Cook for 8-10 minutes until beef is no longer pink and onions are softened.
Add taco seasoning and salsa to the skillet. Stir until well combined.
Add black beans, corn, and diced tomatoes to the skillet. Stir and let simmer for 5-6 minutes.
Incorporate microwaved Ready Rice into the skillet and stir well.
Sprinkle shredded Colby Jack cheese over the top.
Broil in the oven for about a minute until cheese is bubbly and melted.
Let sit for a moment before serving with optional garnishes.