Slice chicken breasts crosswise into ¼-inch strips, ensuring you cut against the grain for maximum tenderness.
In a medium bowl, combine chicken strips with 1 tablespoon cornstarch, ¼ teaspoon salt, and ¼ teaspoon white pepper. Toss until evenly coated and set aside for 10 minutes at room temperature.
Meanwhile, prepare aromatics: julienne ginger, slice garlic thinly, and separate scallions into white parts (sliced thin) and green parts (cut into 2-inch segments).
Prepare cornstarch slurry by mixing 2 teaspoons cornstarch with 1 tablespoon cold water until fully dissolved.
Heat a 12-inch skillet over medium heat for 2 minutes to ensure even temperature distribution.
Add 2 tablespoons oil and heat until shimmering but not smoking.
Add ginger and white parts of scallions, sautéing for 90 seconds until fragrant but not browned.
Add sliced garlic and cook for an additional 30 seconds, stirring constantly to prevent burning.
Increase heat to medium-high and add chicken strips in a single layer without overcrowding (cook in batches if necessary).
Allow chicken to sear undisturbed for 2 minutes to develop proper Maillard reaction.
Stir and continue cooking for 3-4 minutes until chicken is nearly cooked through (155°F internal temperature).
Add Shaoxing wine and use spatula to deglaze pan, scraping up any browned bits (fond).
Add soy sauce, remaining white pepper, and green scallion segments.
Reduce heat to medium-low and simmer for 1 minute.
Re-stir cornstarch slurry and add to pan, stirring immediately to incorporate.
Cook for 60-90 seconds until sauce thickens to coat the back of a spoon.
Remove from heat, add sesame oil, and toss to combine.
Verify chicken has reached 165°F internal temperature before serving.