Place chicken in a large mixing bowl and toss with green onion, cilantro, onion, garlic, ginger, thyme, salt, and pepper. Allow to marinate in seasonings for 30 minutes to 4 hours.
Heat coconut oil in a large stewing pot over medium until shimmering.
Add brown sugar and stir constantly until the sugar melts into a bubbling syrup. Watch carefully to make sure it doesn't burn.
Quick fry the chicken pieces in batches in the caramelized syrup until browned on both sides, about a minute per side. Remove chicken pieces from pot.
Add coconut milk, red pepper flakes, and tomato paste to the pot and mix with the leftover caramelized sugar.
Add the chicken back into the pot and throw in any leftover chopped onion and seasonings from the marinating bowl too.
Stew on medium low for 25-30 minutes, stirring occasionally, until chicken is fully cooked.