Place tofu on a tilted chopping board. Let it stand for 10 to 20 minutes.
To prepare veggies, clean both sides of the green beans and cut into two then boil or steam them for 3 to 5 minutes or until cooked. Set aside. To prepare egg topping, combine all ingredients.
Heat the frying pan with 1 teaspoon of oil and pour egg mixture. Stir consistently (if you can use four chopsticks for mixing, you can make very fine egg crumble). Set aside. To prepare garnish, cut the nori sheet into thin strips using scissors. Set aside. To make teriyaki sauce, combine all ingredients, and then set aside.
To cook tofu, cut the tofu into bite size and pat dry with kitchen paper. Toss tofu lightly in potato starch and shake away excess. Heat the frying pan and place the tofu inside; cook over a medium heat until golden on both sides. Turn off the heat. Wipe excess oil onto a pan with kitchen paper. Pour teriyaki sauce and let it boil with residue of heat. Turn tofu to coat it with sauce. Turn on low heat if the sauce is not thick enough at this stage and simmer to thicken the sauce.
Place the rice into a bowl then arrange egg, teriyaki tofu and beans onto rice. Pour on rest of teriyaki sauce. Top with shredded nori.
Vegan option: Simply serve without egg.