Heat large wok over high heat. Add oil and heat until very hot. Add eggs and scramble over high heat about 20 seconds or until eggs are puffy and cooked through. Add yellow onions and stir 1 minute until translucent, breaking up large pieces of egg with spatula. Add one or more Optional Ingredients and stir 1 to 2 minutes until heated through. Add rice and stir 2 to 3 minutes, breaking up any clumps and tossing until rice is fluffy, separated, and heated through. Add soy sauce and stir until evenly mixed. Add green onions and toss well.