Step 1: Pat the shrimp thoroughly dry with paper towels. Toss with 1 tablespoon of neutral oil, salt, and pepper.
Step 2: Heat a large wok or skillet over high heat until shimmering. Add the seasoned shrimp in a single layer, ensuring not to overcrowd the pan. Cook for 1-2 minutes per side until beautifully charred and opaque. Remove the shrimp from the pan and set aside.
Step 3: Add the remaining 1 tablespoon of neutral oil to the same hot pan. Add minced garlic and grated ginger, stir-fry for 30 seconds until fragrant.
Step 4: Add the mixed vegetables (carrots, peas, bell peppers, etc.) to the pan and stir-fry for 2-3 minutes until tender-crisp.
Step 5: Push the vegetables to one side of the pan. Add the cold day-old rice to the empty side, breaking up any clumps. Let it sit undisturbed for 1-2 minutes to get slightly crispy, then toss it with the vegetables.
Step 6: In a small bowl, whisk together the soy sauce, oyster sauce (if using), and sugar. Pour the sauce over the rice and vegetables, tossing to coat everything evenly. Continue to stir-fry for 2-3 minutes.
Step 7: If using, make a well in the center of the rice, add a tiny bit more oil, and pour in the beaten eggs. Scramble the eggs until cooked, then break them up and incorporate them into the fried rice.
Step 8: Return the charred shrimp to the pan. Add half of the sliced green onions. Toss everything together for another minute to heat through and meld the flavors. Drizzle with toasted sesame oil.
Step 9: Taste and adjust seasonings as needed. Serve immediately, garnished with the remaining fresh green onions.