Prepare for this meal ahead of time by cooking the rice a day before and allowing it to cool in the fridge overnight.
Cut steak into small cubes (about 1/2” or slightly smaller) and place in a Ziplock bag. Combine oyster sauce, garlic, and soy sauce in a small bowl and pour over the steak.
Press around the outside of the bag to evenly distribute the marinade. Press the air out of the bag, seal, and place in the fridge for about 30 minutes. Remove from the fridge and allow to come to room temperature (about 15-20 minutes).
Place cornstarch in a shallow dish and set aside. Remove the steak from the marinade and toss in the cornstarch.
Heat 2 tablespoons oil in a skillet or wok and heat over medium-high heat. When oil is hot and shimmery, add steak in a single layer along the bottom. Make sure it is spread out evenly. Cook for 1-2 minutes and then flip the steak to the other side and cook for another minute. After it has cooked on both sides, stir it all around for another 15-20 seconds, stirring constantly to get even cooking. Remove from the pan and place in a bowl covered with foil. Set aside.
Add remaining oil to the pan and heat over medium-high heat until oil is hot again. Add onion and sauté until onions become transparent. Add garlic and sauté for another minute. Add frozen carrot and peas mixture and sauté until the vegetables become soft and cooked through.
Add beaten eggs to the pan and allow to cook, undisturbed until the eggs start to bubble up and cook on the bottom. Gently stir the eggs until they are completely cooked through.
Add rice a little at a time, breaking apart clumps as you add it. It should be nice and dry from cooling overnight in the fridge. Stir constantly while combining it with the eggs and veggies in the pan. Once all the rice is added continue to stir and flip the rice over until the rice becomes hot. If you find that the rice is sticky, you can try adding a little more oil to the pan or cook on a higher heat. Combine 1 tablespoon oyster sauce, 2 teaspoons soy sauce and white pepper and pour evenly over the rice. Stir until combined.
Add cooked steak to the pan and sauce another minute or two. Serve hot.