1 (1 1/2-pound) whole pork tenderloin
1 cup sliced pineapple in syrup
1/2 cup teriyaki marinade (see recipe, located here)
1/4 cup finely chopped green onions
1/2 teaspoon ground ginger
1/4 teaspoon garlic powder
Cut the pork into slices about 1/4-inch thick and place them in a zippered storage bag.
Drain the pineapple, reserving all of the syrup. In a bowl, combine the syrup, teriyaki sauce, green onions, ginger and garlic powder; pour half of the marinade over the pork, reserving the rest. Cover and refrigerate the pork at least 1 hour.
Meanwhile, prepare the grill for medium-high direct cooking. Remove the pork from the marinade and grill about 5 inches from hot coals for about 5 minutes on each side or until completely cooked.
Pour the pineapple and remaining marinade into a saucepan. Bring it to a boil and serve as a dipping sauce.