Cut Tofu into large cubes. Wrap with paper towels to remove moisture for a few minutes. Slice green onions diagonally and thinly. Mix all the ingredients for Teriyaki sauce in a bowl.
Coat the Tofu cubes with potato starch. Heat oil in a large frying pan at medium heat. Lightly brown all the sides of the Tofu. Remove excess oil with paper towels.
Lower the heat and add the sauce to the pan. Cook for a couple of minutes, stirring to coat the Tofu. Add in green onions.
Put rice in serving bowls, and top with Tofu and the sauce. Sprinkle shredded Nori roasted seaweed if you like.
