Preheat oven to 400°.
Combine first 6 ingredients; stir well with a whisk. Arrange potatoes in a single layer in a 13 x 9-inch baking dish. Pour soy sauce mixture over potatoes. Cover and bake at 400° for 50 minutes or until tender; baste with the soy sauce mixture. Bake, uncovered, an additional 10 minutes or until liquid is absorbed. Sprinkle with sesame seeds.