Start by cutting the boneless skinless chicken breasts or tenders into bite-sized pieces, ensuring even cooking. Coat each piece thoroughly in cornstarch.

In a skillet, heat a tablespoon of olive oil over medium heat. Add the chicken pieces and lightly brown them for about 5-7 minutes.

Once the chicken is browned, transfer it to your slow cooker, spreading it evenly.

In a separate bowl, whisk together the orange marmalade, reduced-sodium soy sauce, white vinegar, sesame oil, ground ginger, minced garlic, and crushed red pepper flakes. Pour this mixture over the chicken in the slow cooker.

Cover the slow cooker and set it to LOW for 2 to 3 hours. Stir halfway through cooking.

After the cooking time is complete, garnish with sesame seeds and serve over rice or with vegetables.