Dice your chicken and place it in a large mixing bowl. Add the corn starch and toss with the chicken to coat.

In another mixing bowl, add the all purpose flour, egg, garlic powder and black pepper. Mix well to combine into a batter. To thin, add 1 tablespoon of water if batter is too thick.

Preheat oven to 400 degrees Fahrenheit. Take a sheet pan and cover it with parchment paper. Add the vegetable oil and spread it evenly over the parchment. Take your chicken breast pieces and dip them in the egg/flour batter until coated. Place the coated chicken on the baking sheet.

Place chicken in the oven and bake for 30 minutes, flipping halfway. Chicken is done when it's crispy on the outside and 165 degrees Fahrenheit internally.

While chicken is baking, make the sauce. In a small pot, mix the marmalade, chicken stock, garlic powder, ground ginger, rice vinegar, and chili flakes (if using).

In a separate dish, mix the corn starch and cold water together (water must be cold) until the corn starch dissolves. Add this corn starch slurry to the orange sauce and stir well to thicken.

In a large mixing bowl, add the crispy baked chicken, and toss with the hot orange sauce. Mix and coat well.

Top the chicken with sesame seeds, green onions, and serve with steamed rice or vegetables.