Pat the chicken thighs dry with a paper towel so the seasoning sticks properly. Sprinkle both sides with salt and black pepper, pressing gently so it stays in place. Set the seasoned chicken aside while you prepare the sauce in a separate bowl.
In a mixing bowl, whisk together the honey, soy sauce, minced garlic, apple cider vinegar, and ketchup until smooth. The mixture should look glossy and slightly thickened once fully combined. This sauce is what transforms plain chicken into something sticky and bold.
Place the chicken thighs in a lightly oiled baking dish in a single layer. Pour the honey garlic sauce evenly over the top, making sure every piece gets a good coating. Use a spoon to spread any extra sauce pooling at the bottom back over the chicken.
Bake the chicken at 400°F for about 30 to 35 minutes, basting once or twice with the pan sauce. The chicken is done when it reaches an internal temperature of 165°F and the glaze looks thick and glossy. If the sauce still looks thin, broil for the last two minutes to help it caramelize.
Let the chicken rest for about five minutes once it comes out of the oven. This gives the juices time to redistribute so the meat stays tender when you cut into it. Spoon any remaining glaze from the dish over the top right before serving.