Gather the ingredients. Have ready the tofu (firm or silken), the green part of the scallion, egg, agedama, tentsuyu (4 parts dashi, 1 part soy sauce, 1 part mirin; diluted store-bought mentsuyu also works), and white rice.
Firm tofu 1 blockScallion (green part) to tasteEgg 1 pieceAgedama (tempura bits) as desiredTentsuyu (4 parts dashi, 1 part soy sauce, 1 part mirin) to tasteWhite rice 1 serving