Serve with a green salad and some cooked rice, and you'll have a complete meal in just minutes. The chicken filling can be made ahead, if desired, but be sure to reheat the mixture and assemble the burritos just before serving.
In a 1-quart microwave-safe bowl, combine chicken, onion, green pepper, tomatoes, garlic, 1 tablespoon cilantro, chili powder, cumin, and salt. Cover and microwave on high for 1 minute. Stir, cover, and microwave on high 1 to 2 minutes longer or until chicken is just cooked through. Stir in cheese. Just before serving, stack tortillas and cover loosely with microwave-safe plastic wrap; microwave 30 to 40 seconds just until warm. With a slotted spoon, place some of chicken mixture on one side of each tortilla; roll up tortillas tightly to enclose filling. Place burritos on a serving platter. Microwave cooking juices remaining in bowl on high for 2 minutes to reduce to about 3 tablespoons. Drizzle reduced juices over burritos, top with remaining cilantro, and serve.