Heat 1 tablespoon of vegetable oil in a large skillet or wok over medium-high heat. Add the shrimp and cook until pink and opaque, about 2-3 minutes. Remove the shrimp from the skillet and set aside.

In the same skillet, add the remaining tablespoon of vegetable oil. Sauté the garlic and onion until fragrant and the onion is translucent, about 2-3 minutes.

Add the frozen peas and carrots to the skillet and cook for another 2-3 minutes until heated through.

Push the vegetables to one side of the skillet and pour the beaten eggs onto the other side. Scramble the eggs until fully cooked, then mix them with the vegetables.

Add the cooked rice to the skillet, breaking up any clumps. Stir in the cooked shrimp, soy sauce, oyster sauce (if using), and sesame oil. Mix everything well and cook for an additional 2-3 minutes until heated through.

Season with salt and pepper to taste. Stir in the sliced green onions just before serving.