Pat the chicken thighs dry with a paper towel and season liberally with salt and pepper. Heat the oil in a large skillet over medium high heat.
Place the chicken thighs in the pan skin side down working in batches, if necessary. (don't crowd the pan or the chicken skin will not get crispy, it will just steam in the pan.) Cook the chicken thighs skin side down for approximately 4-5 minutes or until the skin is golden brown and crispy. The chicken will release easily from the pan when ready to flip.
Flip the chicken over and cook for 4-5 minutes. Transfer the chicken to a plate or platter and drain off all but 2 tablespoons of the remaining juices.
Add the butter to the pan and stir in the garlic. Cook for 1 minute.
Whisk in the honey, chicken stock, vinegar, hoisin sauce and soy sauce. Cook for 2-3 minutes until slightly thickened.
Return the chicken to the pan, turning the thighs to coat with the sauce. Arrange the thighs skin side up and transfer to the oven.
Cook the chicken for 25-30 minutes until crispy and an instant read thermometer registers 165˚F.
Remove from the oven and rest for 10 minutes.
Sprinkle with the sesame seeds and garnish with the green onions, if desired
Serve over rice or noodles with the remaining pan sauce.
Honey Garlic Chicken can be made up to 24 hours in advance. Store in an airtight container in the refrigerator and reheat before serving. For best results, reheat in a skillet with the remaining sauce at 425˚F for 20 minutes or until warmed through.