In a freezer bag or large bowl, combine chicken, lemongrass, salt, ground black pepper, ginger, garlic, brown sugar, vinegar, lemon-lime soda, and lemon juice.
Stir or shake the mixture until every ingredient is well incorporated. Marinade for 1 to 3 hours.
In a bowl, combine margarine, annatto oil, salt, and lemon juice then stir. Set aside.
Grill the chicken while basting generous amount of the margarine mixture.
Transfer the grilled chicken to a serving plate.
Serve with sinamak. Share and enjoy!