Prepare the soup:
Put the following ingredients together. Heat before serving.
Prepare the tofu:
 If you do not have dashi, you can use dilluted memmi in place of the 1 cup of dashi broth and 1/4 cup of soy sauce. Memmi is produced by Kikkoman and is available at most supermarkets. Follow the "Tempura Sauce" or "Somen" instructions on the bottle for preparing 1 1/4 cups of agedashi soup.
If you are using Kikkoman memmi for this recipe, it requires 4 parts water for 1 part memmi, so you would use 1 cup of water and 1/4 cup memmi to get 1 1/4 cups of agedashi soup.