Coat a large nonstick skillet with cooking spray and set pan over medium-high heat. Add egg whites and cook, until scrambled, stirring frequently. Approximately 3 to 5 minutes. Remove from pan and set aside.
Add cooking spray to skillet and place back over medium-high heat. Add scallions and garlic; sauté 2 minutes. Add chicken and carrots; sauté until chicken is golden brown and cooked through, about 5 minutes.
Stir in reserved cooked egg whites, cooked brown rice, peas and soy sauce; cook until heated through, stirring once or twice.