Preheat your oven to 375°F (190°C).
In a large mixing bowl, combine the black beans, corn, cooked rice, salsa, cumin, garlic powder, onion powder, salt, and pepper. Stir until everything’s well mixed.
Transfer the mixture to a greased 8x8 inch baking dish.
Sprinkle the shredded cheese evenly on top.
Bake for 20-25 minutes, or until the cheese is bubbly and slightly golden.
Garnish with chopped green onions if using, and let it cool for a few minutes before serving.