Chicken Braised in Lime and Peanut Sauce

Heat oil in a large Dutch oven over medium-high. Working in 2 batches, cook chicken, skin side down, until golden brown and crisp, 6–8 minutes per batch. Transfer to a plate. Add onion and cook, stirring often, until softened and browned, about 5 minutes. Return chicken to pot and pour sauce over. Add 4 charred lime halves; reserve remaining charred limes for serving. Bring sauce to a simmer. Season with salt and pepper; cover, leaving lid slightly askew. Cook until chicken is very tender, about 1 hour.