1. In a blender combine soy sauce, brown sugar, mirin, honey, fresh ginger, sesame oil and minced garlic and blend until well combined to create marinade.
2. Rinse the chicken and pat dry with paper towel. Place chicken breast-side down. Using sharp kitchen shears, cut along both sides of the backbone, beginning at the back end. Set aside the backbone and giblets for stock, if desired.
3. Using a sharp knife, slice the keel bone at the back of the chicken and crack it open.
Tip: Remove the bone by placing your fingers under it and sliding it out. Doing this will allow the chicken to lay flat when turned over.
4. Place the chicken in a large resealable storage bag and pour in the marinade from Step 1. Seal the bag, making sure there is no excess air inside, and allow to marinate overnight in the refrigerator.
5. Pre-heat grill to 350°F. Place chicken on the grill, skin side up for the first 30 minutes. After 30 minutes, flip the chicken and grill for another 1½-2 hours. Chicken is done when internal temperature reaches 165°F-170°F.
Allow to rest before slicing and serving. Enjoy!
Note: Double the marinade ingredients and combine the second batch with the ½ C. water and ¼ C. cornstarch. Bring to a boil in a medium saucepan, stirring occasionally until thickened to make a dipping sauce.