Gather the ingredients together. Cube the chicken and chop the red bell pepper, if using.
Place the chicken thighs, and red bell pepper (if using) into the slow cooker.
In a medium bowl, whisk together the lime juice and corn starch until smooth.
Add the brown sugar, soy sauce, orange marmalade, salt, pepper, and ginger to the bowl. Mix well and pour over the chicken. Stir.
Add the drained pineapple chunks (save the juice for another recipe) and stir.
Cook on Low for 3-4 hours or on High for 2-3 hours, or until the chicken is cooked.
Stir in half of the green onion slices.
Serve over hot cooked rice and garnish with with the remaining green onions, and sesame seeds (if using).