Gather your large wok or skillet, a spatula, a sharp knife, and a small bowl to keep your prepped ingredients ready.
Heat 2 tablespoons of oil over medium-high heat until shimmering and just starting to ripple, then add the sliced mushrooms in a single layer. Let them sear undisturbed for about 2-3 minutes until their edges turn dark and they release a rich aroma.
Flip or stir the mushrooms to cook the other side for another 2 minutes, until evenly browned and slightly crispy at the edges. Remove them from the pan and set aside.
If you're using eggs, crack them into the hot pan now and scramble gently, cooking for about 30 seconds until just set, then push to one side of the pan. Remove if cooked through or leave for a more integrated scramble.
Add another teaspoon of oil if needed, then toss in the minced garlic. Cook for 30 seconds until fragrant and slightly golden, stirring constantly to prevent burning.
Break up the cold, day-old rice with your hands or a spoon, then add it to the pan. Stir vigorously to coat the rice with garlic and oil, spreading it out evenly. Increase the heat to high and stir-fry for 2-3 minutes until the rice is hot, slightly crispy, and begins to shimmer.
Return the cooked mushrooms to the pan, mixing thoroughly to distribute evenly. Stir-fry together for another 2 minutes, allowing the flavors to meld and the rice to develop a slight crust.
Pour in the soy sauce and drizzle with sesame oil, tossing everything well to coat and season evenly. Add sliced green onions at the last moment and cook for another minute until fragrant and glossy.
Turn off the heat and let the fried rice rest for a minute to allow the flavors to settle. Serve hot directly from the pan, garnished with extra green onions if desired.
