In a big bowl, rehydrate the wakame with an important amount of cold water for 10 minutes.
Put the semolina for couscous in a bowl and add the same amount of boiling water.
Add dashi, cover and let cook for 5 minutes. Meanwhile, drain wakame, wash the herbs, remove the stems and chop the ingredients finely. Dice the tomatoes.
In a salad bowl, add the cooked semolina, herbs, wakame and tomatoes then mix with the 5 yuzu juice tablespoons and olive oil.