Start with day-old rice if possible; it helps achieve the perfect texture. If using freshly cooked rice, spread it out on a baking sheet to cool and dry slightly.
Heat the vegetable oil in a large skillet or wok over medium-high heat. Once hot, add the minced garlic and sauté for about 30 seconds until fragrant.
Push the garlic to the side of the pan and crack the eggs into the skillet. Scramble them gently until fully cooked, then mix them with the garlic.
Add the diced chicken (or your choice of protein) to the skillet and cook for another 2-3 minutes until heated through.
Stir in the mixed vegetables and cook for an additional 2 minutes until they are just tender.
Add the rice to the skillet, breaking up any clumps. Stir everything together.
Pour in the soy sauce and oyster sauce (if using), and mix thoroughly until the rice is evenly coated. Cook for another 2-3 minutes, stirring continuously.
Add sliced green onions, and season with salt and pepper to taste. If desired, finish with a drizzle of sesame oil for extra flavor.
Serve hot, garnished with additional green onions if desired.