In a microwave-safe dish, mix together the cooked rice, diced chicken, and thawed vegetables. Drizzle olive oil over the mixture, ensuring it is evenly coated to prevent sticking. Cover the dish loosely with a microwave-safe lid or plastic wrap, leaving a small vent for steam to escape.

Drizzle soy sauce over the mixture, then sprinkle garlic powder, onion powder, and salt evenly. Stir thoroughly to ensure the seasonings are well distributed, coating every piece. The aroma should be fragrant, and the mixture should appear evenly seasoned, with no clumps of spices visible. This step enhances the overall flavor profile.

Place a microwave-safe lid or plate over the dish to retain steam, promoting uniform cooking and preventing the rice from becoming dry. Microwave on high for 5 minutes, then check if the rice is tender and the vegetables are heated through. If needed, continue microwaving in 1-minute intervals until done.

Observe the dish for dryness. If it seems lacking moisture, incorporate a tablespoon of water and mix thoroughly. This step helps to keep the rice tender and prevents it from hardening, ensuring a pleasant texture throughout the dish. Stir well to distribute the moisture evenly.

Microwave the dish for an additional 2-3 minutes on high power. As it heats, you should notice the spices releasing their aroma more intensely. The vegetables should be tender, and the chicken should be thoroughly warmed. Stir the mixture halfway through to ensure even heating and prevent any cold spots.

Carefully check the internal temperature of the pre-cooked chicken using an instant-read thermometer. Ensure it reaches at least 165 F (74 C) to confirm it is safe to eat. Insert the thermometer into the thickest part of the chicken, avoiding any bones, for the most accurate reading possible.

Carefully take the dish out of the microwave, using oven mitts if necessary to avoid burns. Keep it covered and let it rest for 1-2 minutes. This pause allows the ingredients to integrate better and the dish to cool slightly, ensuring a more even temperature throughout.

Sprinkle additional black pepper over the dish to enhance its visual appeal and add a subtle kick. The pepper's aroma will complement the other ingredients, creating a more inviting meal. If you prefer, you can also add a touch more black pepper to suit your taste, ensuring a balanced seasoning.

Transfer the cooked dish to a plate and serve immediately while still warm. The soft texture of the rice complements the tender chicken, providing a pleasing contrast. Enjoy the vibrant colors of the mixed vegetables, which add visual appeal. Ensure the dish is consumed promptly to maintain its warmth and texture.