Prepare the marinade by combining all ingredients in a bowl.
Place chicken thighs in a large resealable bag or dish, pour marinade over them, and refrigerate.
Preheat your oven to 375°F (190°C).
Remove the chicken from the marinade, reserving the marinade for later use.
Place the chicken on a baking sheet lined with parchment paper, skin side up.
Bake the chicken in the preheated oven for about 25-30 minutes.
Baste the chicken with the reserved marinade halfway through cooking.
Broil for the last 5-10 minutes to achieve a crispy exterior.
Let the chicken rest for 5-10 minutes before slicing.
Slice, serve, and enjoy your homemade Char Siu chicken!