Preheat the oven to 400°F (200°C). Pat the chicken thighs thoroughly dry with paper towels.
Season the chicken on all sides with salt, black pepper, garlic powder, and paprika.
Arrange the thighs skin-side up in a large baking dish, leaving a little space between each piece when possible.
In a small bowl, whisk together the Dijon mustard, honey, olive oil, and dried thyme until smooth and well combined.
Spoon the honey mustard mixture evenly over the chicken thighs, lightly coating each piece.
Bake uncovered for 35–40 minutes, or until the chicken reaches a safe internal temperature of 165°F (74°C) at the thickest part without touching the bone.
Switch the oven to broil. Broil for 2–4 minutes, watching carefully, until the skin is lightly browned and the honey mustard glaze looks glossy and caramelized.
Remove the Honey Mustard Chicken Thighs from the oven and let them rest for 5 minutes.
Spoon some of the flavorful pan sauce over the chicken and garnish with fresh thyme or parsley before serving, if desired.