Heat the oven to 375 F and grease a 9 by 13 inch baking dish.
Warm the olive oil in a large skillet over medium heat. Add the onion and bell pepper and cook until soft. Stir in the garlic.
Add the black beans, corn, tomatoes, cooked rice, cumin, chili powder, smoked paprika, oregano, salt, and pepper. Stir until the mix looks even and hot.
Taste and adjust the salt. Pull the skillet from the heat and stir in half of the cheese and half of the cilantro.
Spoon the mix into the baking dish. Top with the rest of the cheese.
Bake until the cheese melts and the edges bubble. This takes about 20 minutes.
Let the casserole rest for 5 minutes. Squeeze the lime over the top and finish with the rest of the cilantro.
Serve warm with sour cream and green onions.