Heat a large stainless-steel skillet with a lid over medium heat. Remove the chicken from the marinade, reserving the liquid. Place the chicken skin side down in the skillet and sear until deeply browned, 5 to 7 minutes. Turn and cook until browned on the second side, 3 to 4 minutes more, reducing the heat as needed to prevent burning from the sugar.

Transfer the chicken to a plate. Add the onion to the skillet and cook, stirring occasionally, until softened and lightly caramelized, about 5 minutes.

Return the chicken to the skillet, skin side up, nestling it among the onions. Pour in the reserved marinade and add the broth. Bring to a simmer, then cover and cook over medium-low heat until the chicken is very tender and an instant-read thermometer inserted into the thickest part registers at least 175°F/80°C, 25 to 35 minutes.

Uncover and simmer briefly, if needed, until the sauce is glossy and slightly thickened. Spoon the onions and sauce over the chicken and serve hot, preferably over steamed white rice.