Heat the oil in a large nonstick skillet over MEDIUM heat (you’ll use the same skillet to cook the burritos so it needs to be at least 12-inches). Sauté the onion and bell pepper until tender, about 3 to 4 minutes. Remove the skillet from the heat.
Place the cooked rice and black beans in a large bowl and add the cooked veggies. Add the lime juice and toss to combine. Season with the cumin, chili powder, garlic powder, salt and pepper, and toss again. Set aside.
Sprinkle the cheese over a tortillas, leaving a ½-inch border around the edges (should cover whole tortilla with a little empty border), then spoon an equal amount of the rice and bean mixture down the center of each tortilla. Top with the chicken.
Fold the sides of one of the tortillas in and over the filling about 1- to 2-inches (this will close the ends and prevent the filling from falling out). Now fold the bottom over the filling and roll it up. Repeat to roll remaining burritos.
Wipe the skillet down with a paper towel and coat with nonstick cooking spray. Return it to MEDIUM-LOW heat.
Spray the seam side of burritos with nonstick cooking spray. Set two burritos, seam-side down in the skillet (I can fit two side by side in my large skillet) and press them lightly with a spatula to press them down and help them seal (don’t totally flatten, just press lightly). Cook until golden brown and crisp, 2 to 3 minutes.
Spray the tops with nonstick cooking spray and flip. Cook for another 2 to 4 minutes until golden and the filling is warmed through. You can roll and hold in place, if needed, so that all sides are toasted.
Transfer the burritos to a cutting board and slice them in half. Repeat with remaining burritos.
Serve with sour cream, salsa, or hot sauce for dipping.