According to some sources, "yaki" (Japanese) refers to the method of cooking - grilling or broiling - while "teri" refers to the glaze. However, it is not an authentic Japanese dish, but most likely developed as Japanese immigrants settled in Hawaii. My recipe is an adaptation of Joy of Cooking's marinade.
Chicken Teriyaki
Ingredients
1 cup soy (lite or regular)
1/2 cup oil
2-3 tablespoons brown sugar
3 teaspoons diced garlic (or 3 cloves, minced)
1 teaspoon dried ginger or 1 tablespoon fresh grated ginger root
1/2 teaspoon dried onion powder or 1/4 cup fresh onion, diced small
1 tablespoon prepared mustard
6-8 boneless skinless chicken breasts
Directions:
Rinse and pat dry breasts and place in large zip-lock bag or glass pan deep enough to hold them and the marinade.
Whisk the marinade ingredients together. You can heat on the stove or in the microwave to melt the brown sugar, but I rarely take that added step. Pour marinade over breasts and turn to coat. Allow to marinate for at least 30 minutes, or several hours or overnight. The longer it marinates, the more intense the flavor, but even just 30 minutes of marinating on the kitchen counter while the grill heats up will still yield good results if you're pressed for time.
Remove from marinade and grill over medium-high heat. For large, thick chicken breasts, I grill for approximately 15 minutes, turning after 5 minutes, again at the 10 minute mark, then at least once or twice more, just until juices run clear. (I'm not a fan of overcooked chicken, so I tend to pull mine off the grill sooner than later.) The cooked breasts can be sliced and served over a garden salad for a light dinner or lunch.
Note: You can also use this marinade on chicken thighs, a whole cut-up chicken, or steaks (it's a great way to tenderize and season some less-than-perfect cuts of meat.) I don't recommend freezing the uncooked meat in the marinade - I tried it once and the results were too salty.