Heat a sauté pan over medium heat and add sunflower oil and one tablespoon sesame oil. Once heated, add the onion and sauté for five minutes, until golden.

Add the sliced vegetables and cook for a few minutes, stirring occasionally, until they’re tender yet still slightly firm. Transfer the vegetables to a large bowl.

In the same pan, add the remaining sesame oil and soy sauce. Sauté chicken until fully cooked and no longer pink. Return the vegetables to the pan, stir to combine, and cook for a few more minutes to bring everything together.