Mix 1/4 cup cornstarch, salt, and pepper together in a gallon-sized bag. Add the chicken pieces, seal the bag, and shake until the chicken is well coated.
Heat the oil in a large nonstick skillet over medium-high heat until shimmering, about 3 minutes. Add the chicken in batches, making sure not to crowd the pan, and cook about 2 minutes per side. The chicken might not brown, but the cornstarch coating will become crispy and dry. The chicken will not be completely cooked at this point, and that is OK. Transfer the chicken to a 6-quart slow cooker and repeat with any remaining chicken.
Whisk the sugar, rice vinegar, soy sauce, cider vinegar, sesame oil, 1 Tbsp cornstarch, garlic, ginger, and pepper flakes together in a small bowl. Pour over the chicken, then scatter the dried chile peppers around the chicken.
Cover and cook until chicken reaches 165F, 1 1/2 to 2 hours on the LOW setting or 45 minutes on the HIGH setting. Toss the cooked chicken with the sauce. Serve with rice. Enjoy!
Remove the beef from the fridge and set out at room temp while you make the sauce. Place the orange juice, soy sauce, sesame oil, brown sugar, cornstarch, garlic, 1/2 tsp salt, and red pepper flakes in a small bowl and whisk to combine. Set aside.
Heat 1/2 Tbsp. oil in a large frying pan over high heat until shimmering. Add the beef and season with the remaining 1/2 tsp. salt and pepper. Press the meat into an even layer and cook undisturbed until the bottom is brown and crisped, about 4 minutes. Break up the meat with a wooden spoon, then press it into the pan to help it brown. Cook until well-browned and crisp all around, 3-4 minutes. Transfer to a large paper towel lined plate.
Drizzle the remaining olive oil around the pan. Add the orange zest, onion, and red pepper, and cook, stirring until slightly tender, about 3 minutes. Rewhisk the sauce, pour into the pan, and stir to coat the vegetables. Bring to a boil and cook until thickened, about 1 minute. Return the beef to the pan and stir to combine. Serve over rice and top with scallions. Enjoy!