Cut the chicken breasts into roughly 1-inch cubes.
Heat the avocado oil in a large frying pan over medium-high heat. Add the chicken and cook for approximately 10–15 minutes, turning regularly, until browned on all sides and cooked through.
While the chicken is cooking, whisk together the soy sauce, honey, sesame oil, ginger, garlic powder, white wine vinegar, lemon juice and sesame seeds.
Once the chicken is cooked, remove it from the pan and set aside.
Pour the sauce into the same pan. There's no need to clean it first – those lovely browned bits from the chicken will add even more flavour.
Mix the cornflour with a little water in a small bowl to make a smooth slurry. Add this to the sauce and stir continuously over medium-high heat until the sauce thickens and becomes glossy. This happens quickly, so don't wander off to check Instagram.
Add the cooked chicken back into the pan and toss well until every piece is coated in the sticky sauce.
Serve immediately with steamed vegetables and your choice of rice or quinoa.