While soaking the salmon roe in about 40°C water, peel off the thin skins and disperse the eggs.
Drain in a colander and gently use a knife to cut off tje remaining membrane.
Place the roe in a dish, add the flavoring ingredients, and marinate for at least 5 hours.
Here is what the salmon roe looks like at 5 hours. They become nice and plump.
Put some rice in a dish, place the shiso leaves on top, and then top with the salmon roe, wasabi, and nori. Pour on some soy sauce and serve.
Salmon Roe with Salmon Filet over Rice: https://cookpad.com/en/recipes/143604-ikura-salmon-roe-oyakodon
Dashi Soy Sauce: https://washoku.cookpad.com/recipe/1820595