Preheat your oven to 400°F (200°C) and grease a 9 x 13-inch baking dish with olive oil.

Trim the tops of three red bell peppers and remove the seeds. Slice two in half lengthwise.

In a large skillet, heat olive oil and sauté diced onion for about 4 minutes until translucent.

Stir in rice, salt, vegetable stock, diced tomatoes, and green onions. Bring to a boil, cover, and simmer for 25 minutes.

Fold in black beans and corn once the rice is cooked, mixing well.

Stuff each halved pepper with the filling and top with shredded cheese.

Bake uncovered for about 40 minutes until cheese is melted and peppers are tender.

Garnish with minced cilantro before serving.