If the tuna is already cut into slices or in chunks, use as is. If using a slab, thinly slice into 5 mm.
Combine the sauce ingredients in a container, and place the sliced tuna. Leave in the fridge for about 2 hours.
Put hot rice in a bowl. Place 5 leaves of washed and pat-dried shiso, and marinated tuna on top. Garnish with the chopped scallions and drizzle the sauce over.
Story Behind this Recipe
After many experiments, I settled on this recipe. If you like scallions or shiso leaves, this is your recipe!
I prefer not to use nori seaweed for garnishing. Reserve some of the sauce and scallions and sprinkle on top!