Add ⅓ cup brown sugar, ¼ cup low-sodium soy sauce, ¼ cup water, 2 teaspoons garlic powder, and 1 teaspoon onion powder to a saucepan and heat on medium until the sugar dissolves, whisking as it cooks.
Pour about half the sauce into a large cast iron skillet or baking dish.
Set 3 pounds skin-on, bone-in chicken thighs skin side-up in the sauce, then pour the remaining sauce over the chicken.
Bake in the preheated oven for 30-35 minutes, until the chicken is cooked through to 165°F.
Spoon the sauce over the chicken and serve!
Notes
You can sub in boneless thighs—just cook for 20-25 minutes instead of 30-35 minutes.
We used light brown sugar, but you can use dark brown sugar as well.
Store leftovers in an airtight container for up to 3 days. Chop up the chicken to add to salads or wraps, too!