In a small bowl, whisk together oyster sauce, rice vinegar and red pepper flakes.
Season chicken with 1/2 teaspoon salt and 1/4 teaspoon pepper.
Heat 1 tablespoon vegetable oil in a large cast iron skillet over medium high heat. Working in batches, add chicken to the skillet in a single layer and cook until golden brown, about 7-8 minutes; set aside.
Add onion, mushrooms and carrots to the skillet. Cook, stirring occasionally, until tender, about 3-4 minutes.
Stir in garlic and ginger until fragrant, about 1 minute.
Stir in green peas until heated through, about 1-2 minutes; set aside .
Heat remaining 1 tablespoon vegetable oil and sesame oil over medium high heat.
Spread rice in an even layer. Cook, without stirring, for 2 minutes. Flip and spread in an even layer again, cooking for an additional 2 minutes.
Push rice to one side of the skillet; add eggs to opposite side of the skillet, and cook, stirring often, until thickened and no visible liquid egg remains, about 2-3 minutes.
Stir in chicken, vegetables and oyster sauce mixture until well combined, about 2-3 minutes. Continue cooking, stirring constantly, until flavors have blended, about 3-5 minutes.
Serve immediately, garnished with green onions and sesame seeds, if desired.
Notes
Prep ahead of time. Save time by cooking the rice and dicing the vegetables 1-2 days prior, storing in airtight containers in the fridge.
Oyster sauce is key. Oyster sauce, the secret ingredient here, will add a rich, savory umami flavor to the fried rice – slightly sweet and salty, and will not taste strongly of oysters.
Use your favorite protein. Chicken thighs, chicken breasts, pork or shrimp will all work very well here.
Swap, omit, or add as many vegetables. Broccoli, green beans, spinach, asparagus, cabbage and snow peas are all great additions.
Day-old rice is best. Use leftover chilled long grain rice. Fresh rice will be too moist and will turn to mush.
Substitute brown rice. Brown rice will have more nutritional benefits than white rice (more fiber and vitamins), add nutty flavors, and does not require pre-chilling to dry out properly, allowing you to use fresh brown rice if needed.
Avoid sticky rice. Avoid short-grain, sticky or sushi rice as they can clump and become gummy.
Add garnishes. Make it restaurant-quality by adding simple garnishes such as green onions and sesame seeds.