Marinate the Chicken
In a large, nonreactive bowl or resealable plastic bag, combine the coconut milk, soy sauce, rice vinegar, garlic, bird’s-eye chilies, bay leaves, and black pepper. Add the chicken thighs and turn to coat thoroughly. Refrigerate for a minimum of two hours, or ideally overnight, allowing the chicken to absorb the rich flavors.
Cook the Chicken
Transfer the marinated chicken along with the sauce to a large Dutch oven or pot. Place over high heat and bring to a boil. Once boiling, reduce the heat to a simmer and cook for approximately 30 minutes, stirring occasionally, until the chicken is fully cooked and tender.
Reduce the Sauce
Preheat the broiler. Remove the chicken pieces from the pot and place them in a large bowl. Raise the heat under the pot to medium-high and allow the sauce to reduce for about 10 minutes, or until it reaches a consistency similar to heavy cream. Remove the bay leaves and chilies at this stage.
Broil the Chicken
Place the chicken pieces on a roasting pan and broil for 5 to 7 minutes, or until the edges begin to caramelize. Turn the chicken, baste with the reduced sauce, and broil for an additional 3 to 5 minutes. Once finished, return the chicken to the pot, allowing it to cook for a few more minutes in the sauce. Serve the chicken on a platter, drizzling it generously with the rich sauce.