Heat the oil in a large non-stick pan. Add chicken pieces, black pepper and salt. Stir and cook for 5 minutes until the chicken is seared. Drain the chicken pieces and keep warm.

Meanwhile, combine vinegar, cornstarch, orange zest and orange juice in a bowl.

Add garlic to the drippings in the pan and cook until fragrant. Add the orange juice mixture and cook until it thickens. This may takes 3-4 minutes.

Add chicken pieces and glaze them in the sauce for about 5 minutes, stir occasionally.