Make the annatto oil: In a large skillet, heat the oil and the annatto seeds. Stir, cooking on medium heat, for 2-3 minutes. Carefully pour the oil mixture into a heatproof glass measuring cup or other container with pouring spout and set aside to cool slightly.
Make the marinade: In a large bowl, whisk together half of the annatto oil (about ¼ cup of the oil) and set the rest aside for later. To the bowl, add the soy sauce, vinegar, calamansi juice, lemon lime soda, lemongrass, garlic, ginger, salt, and pepper.
Add the chicken to the marinade, tossing to coat all sides. Cover and refrigerate for at least 4 hours and up to overnight.
Take the chicken out of the refrigerator about 20 minutes before you are ready to grill. Lightly brush the grill grates or an indoor grill pan with olive oil.
Using a separate basting brush, brush the remaining annatto oil over the chicken and then place on the grill. Grill the chicken over medium-high heat (450° - 500°F) for approximately 4-6 minutes on each side, until the chicken is fully cooked. Chicken is cooked when a meat thermometer shows an internal reading of 165°F.
Garnish with chopped fresh cilantro, if desired.
Notes
makes approximately 6-8 servings.Serve with riceSubstitutions:
You can substitute annatto paste for the annatto seeds. If doing so, you'll need to smash down and separate the paste to make the oil. Once heated and mostly combined, you can carefully add the mixture to a blender and blend until it's more smooth.
You can use chicken breasts instead of chicken thighs, but thighs will be more flavorful and juicier.
Substitute rice wine vinegar or regular white vinegar for the cane vinegar, if you can't find cane vinegar.
For the lemon lime sparkling water or soda, you can use Sprite, 7-Up, or Calamansi sparkling water.
If you can't find calamansi juice, you can use a mixture of freshly squeezed lemon juice and lime juice (50/50 ratio).
Use lemon zest or lime zest as a substitute for lemongrass.