Preheat your oven to 425 degrees Fahrenheit. Line a rimmed baking sheet with parchment paper and set aside.
Wash the peppers and cut them in half lengthwise. Remove the ribs and seeds. Place the peppers cut side down on the prepared baking sheet. Rub them lightly with olive oil and roast them for 8 minutes. When done baking reduce the oven to 350 degrees Fahrenheit.
4 poblano peppers, 1 tablespoon olive oil
While the peppers cook, heat a large skillet over medium heat, add the ground beef and break up. Once the beef has just begun to brown, add the onion and garlic. Sauté until the onion is soft, about 5-7 minutes. Drain off any excess grease. Season with the chili powder, cumin, and paprika.
1 pound ground beef, 1/2 medium yellow onion, 2 garlic cloves, 2 teaspoons chili powder, 2 teaspoons kosher salt, 1 teaspoon cumin, 1/2 teaspoon paprika
Stir in the cooked rice, black beans, tomato sauce, green chiles, and 1 cup of the cheese. Taste the mixture and add more salt and pepper to taste. Divide the mixture between the roasted poblano peppers. Top with the remaining cheese.
1 cup cooked rice, 1 cup black beans, 15 ounces tomato sauce, 4 ounces green chiles, 2 1/2 cups Monterey Jack cheese
Bake uncovered for 25 minutes. Serve immediately.