The day before: Don't skip this step! Cold rice is the secret to great fried rice. Freshly cooked rice is too soft and will become mushy on the griddle, while chilled rice stays separate and develops those delicious crispy bits.
Rinse the jasmine rice in a fine-mesh strainer until the water runs mostly clear.
Instant Pot Method: Add the rinsed rice and water to the Instant Pot. Cook on High Pressure for 4 minutes. Allow the pressure to naturally release for 10 minutes, then carefully release any remaining pressure.
Stovetop Method: Add the rinsed rice and water to a medium saucepan. Bring to a boil, then reduce the heat to low, cover, and cook for 15 minutes. Remove from the heat and let stand, covered, for 10 minutes.
Spread the cooked rice onto a parchment-lined baking sheet in an even layer. Let cool slightly, then transfer to the refrigerator and chill overnight, or for at least 2 hours.
Make the Chicken Fried Rice: Mix together the butter and garlic. Set aside. Preheat the Blackstone to high heat. Season the chicken with the kosher salt and white pepper.
Add 1 tablespoon sesame oil to the griddle. Add the chicken and cook for 4-5 minutes per side, until very golden brown and cooked through. Transfer the chicken to a cutting board and roughly chop into bite-sized pieces.
Add another tablespoon sesame oil to the griddle. Add the cold rice and spread it into an even layer. Let it cook undisturbed for 2-3 minutes before stirring. Pour half of the butter mixture over the rice and add the scallions. Continue cooking for 4-5 minutes, breaking up any clumps and allowing some of the rice to become lightly crisp.
Meanwhile, add another tablespoon sesame oil to the griddle and add the peas and carrots. Cook for 3-4 minutes, until completely heated through. Pour the remaining half of the butter mixture over the vegetables.
Use your spatula to make a large well in the center of the rice. Add the remaining 1 tablespoon sesame oil to the well, then pour in the beaten eggs. Season with salt and white pepper. Scramble the eggs until they're just cooked through, then mix them into the rice until evenly distributed.
Mix the peas and carrots, scrambled eggs, and chopped chicken into the rice. Drizzle the soy sauce over the mixture and toss everything together until evenly combined. Continue cooking for 2-3 minutes, stirring frequently, until everything is heated through and the rice has absorbed the sauce.
Taste and add additional soy sauce, salt, or white pepper as desired before serving.