Preheat oven to 325℉. Cut chicken breasts into bite-sized pieces. Dry the chicken with a paper towel to help the coating stick, then season with salt and pepper.
Add cornstarch to a bowl and a beaten egg to a separate bowl. Dip chicken into cornstarch, then coat in egg mixture.
Heat canola oil in a large skillet over medium-high heat and cook chicken until browned. Place the chicken in a 8x8 greased baking dish.
In a medium bowl, whisk together brown sugar, orange juice, orange zest, soy sauce, sriracha, white vinegar, apple cider vinegar, grated ginger, garlic powder, and cornstarch. Pour over chicken and bake for 1 hour. Stir a couple of times during the cooking process. The sauce will thicken and start to caramelize as it cooks.
Allow to sit at least 5 minutes after pulling to allow the sauce to thicken. Serve over rice.