Pat the tofu dry with a kitchen towel and cut it into rectangles.
Cut the chicken breast into bite-sized pieces.
Heat cooking oil in a pan and grill the tofu and chicken breast until golden brown on both sides.
Place the grilled tofu and chicken breast on top of the rice.
Mix soy sauce, sugar, and water to make the sauce, then boil it in a pan.
Pour the sauce over the rice and toppings.
Drizzle with mayonnaise and garnish with chopped green onions and shredded seaweed to finish.