Heat 1 tablespoon of oil in a large nonstick pan over medium-high heat. Add the chicken and fry until fully cooked, about 3 minutes. Remove to a plate and set aside.
Add another 1 tablespoon of oil to the pan. Add the eggs and quickly scramble them with a spatula. When the eggs are no longer runny, remove to the same plate as the chicken.
Add the remaining 1 tablespoon of oil to the pan. Add the frozen mixed vegetables and cook until warm, 2 minutes.
Add the rice and cook until it's warm, 1 minute.
Add back the chicken and eggs. Drizzle the soy sauce, sesame oil, and scallions, and toss until the rice is evenly coated. Enjoy!