Preheat oven to 375°. Cut chicken into strips. Heat a medium skillet over medium-high heat. Coat pan with cooking spray. Add chicken; sauté 1 minute. Remove chicken. Add onion, red bell pepper strips, and yellow bell pepper strips to pan; sauté 5 minutes. Stir in flour and cumin; cook 1 minute. Add chicken broth, stirring until smooth. Cook 2 minutes. Add pepper Jack cheese; stir until smooth. Remove from heat; stir in chicken and cooked brown rice. Spoon mixture into an 11 x 7inch glass or ceramic baking dish. Sprinkle mixture with Monterey Jack cheese; bake at 375° for 25 minutes.