Marinate the Chicken: In a mixing bowl, combine the boneless chicken thighs with soy sauce, dark soy sauce, minced garlic, cornstarch, and rice wine. Mix well and marinate for 15 minutes at room temperature.

Cook the Chicken: Heat olive oil in a non-stick pan over medium heat. Add marinated chicken strips in a single layer and cook for 5 minutes until golden brown and fully cooked.

Sauté the Vegetables: In the same pan, add more oil and sauté the sliced onion and shredded carrot for about 5 minutes until tender and slightly caramelized.

Combine Ingredients and Finish: Return chicken to the pan, add chopped spring onion, and stir-fry for another 20-30 seconds. Drizzle with rice wine before serving.