This recipe comes from my dad who served his mission in Japan. He got it from a local RS President in trade for his banana cream pie recipe. It is a family favorite often served with a Japanese curry over rice and Yakisoba (I have the recipe for this also, but is too complicated to post here, I'd have to show you in person).
2 c. Soy sauce
2 c. brown sugar
1/2 c. Aji Mirin (sweet rice wine, found in Asian markets. 1 T. Lemon Juice can be substituted)
1-1/2 t. minced garlic
1 t ground ginger (fresh minced ginger gives a bolder flavor)
Stir until syrupy and sugar is dissolved. Pour over chicken and cook skin side down for 1-1½ hour at 350. Turn skin side up and cook for an additional 15 minutes. This makes enough sauce for a 9x13 pan. You can reserve some of the sauce to serve with rice, otherwise discard it.