Season the chicken with garlic powder, onion powder, salt, and black pepper.
Spray a nonstick skillet with cooking spray and add the chicken. Cook the chicken for 5 minutes or until no longer pink. Stir in the buffalo sauce and continue cooking for 2 minutes.
To assemble the bowls, add 1/2 of the rice, lettuce, cucumber, celery, pickled red onions, buffalo chicken, and green onions.
Drizzle 1 tablespoon of light ranch over each bowl. Enjoy!