The Starch Separation Prep: Pull your day-old, chilled cooked rice directly from the refrigerator. Use clean hands to gently break apart any large blocks or clumps inside the bowl until every grain is loose and completely individual. Pro Tip: Rushing this dish with freshly boiled, hot rice is a recipe for disaster. Fresh rice is packed with surface moisture that will immediately turn into a gummy, gluey mash when combined with sauces in the pan. Chilling the rice overnight triggers retrograde starch crystallization, drying out the exterior coat of the grains so they fry up crisp, chewy, and separate.

Add exactly 1 tablespoon of the toasted sesame oil to a large, heavy-bottomed skillet or wok over medium-high heat.

Once the oil is shimmering hot, toss in the chopped yellow onion and the mixed frozen vegetables. Sauté for 3 to 4 minutes, stirring constantly, until the onions soften and turn translucent and the vegetables have released their frozen frost.

Drop the stove heat down to medium. Add the minced garlic to the pan and sauté for exactly 30 seconds just until fragrant. Do not let the garlic burn, or it will turn bitter.

The Clean-Pan Egg Scramble: Use a wooden spoon or spatula to aggressively shove all the sautéed vegetables over to one far side of the skillet, leaving half of the pan surface completely bare. Crack the 2 large eggs directly onto the cleared, hot metal. Stir them immediately with your spoon to break the yolks and scramble them thoroughly. Let them cook undisturbed for 60 seconds until completely set but still tender.

Chop the cooked egg ribbons into bite-sized pieces with the edge of your spatula, then stir-fry them directly into the surrounding vegetable pile until everything is unified.

Turn the burner heat back up to high. Dump the loose, cold rice and the pre-cooked diced chicken thighs straight into the skillet.

The High-Heat Flash: Drizzle the remaining 1 tablespoon of sesame oil and the ¼ cup of soy sauce evenly over the entire pan. Toss and stir the rice continuously for 2 to 3 minutes, lifting the ingredients from the bottom and flipping them. Crucial: Frying on high heat at this exact final stage flash-evaporates the liquid from the soy sauce instantly, forcing the savory umami notes to fuse onto the exterior shells of the dry rice grains without making them soggy. Garnish with fresh green onions and serve immediately.