1. Begin by marinating the boneless chicken pieces. Combine soy sauce, sesame oil, minced garlic, ginger, and lime zest in a large bowl, ensuring each piece of chicken is well-coated. Refrigerate for at least 30 minutes or longer for enhanced flavor.
2. While the chicken marinates, prepare the peanut butter sauce by whisking peanut butter, hoisin sauce, coconut milk, honey, chili flakes, and lime juice in a medium bowl. Blend until the sauce is smooth and consistent.
3. Remove the marinated chicken from the refrigerator and heat a skillet over medium heat with sesame oil. Cook the chicken in batches for 5-7 minutes per side, ensuring a golden-brown exterior and fully cooked interior.
4. Once the chicken is cooked, pour the peanut butter sauce into the skillet, ensuring the chicken pieces are evenly coated. Lower the heat and let it simmer for 10-15 minutes, allowing the flavors to meld together. If needed, thicken the sauce by mixing cornstarch with water and stirring it into the dish.
5. Remove the skillet from heat once the sauce reaches your desired consistency. Garnish the chicken with sesame seeds and chopped green onions for added flavor and presentation.
6. Serve the Peanut Butter Chicken with sides like jasmine rice, fresh salad, or grilled vegetables for a complete and well-balanced meal.