Finely chop 4 cloves of garlic and set aside.Prepare the chicken thigh: debone if necessary, rub a little oil, half a tablespoon of light soya sauce, half a tablespoon of dark soya sauce and half a teaspoon of sugar on both sides. Add half a tablespoon of mirin to make it authentic, but it's ok without. Then grill in an oven for 10 min skin-side down and 5 min skin-side …