Cook the sushi rice as per packet instructions. Make sure you leave the lid off while it comes to a boil, then place the lid on and don’t stir while simmering.
In a small bowl, mix together the rice wine vinegar, sugar and salt. Once the rice has cooked, place it in a large bowl or spread out on a lined tray. Drizzle the rice wine vinegar mix on the rice and stir through. It will absorb the liquid.
For the dressing: Mix all the ingredients together. Pour half the dressing over the diced tuna and mix well.
To assemble the poke bowl: Divide the rice into two bowls, then top with the tuna, cucumber, edamame, spring onion and sesame seeds. Drizzle over the remaining dressing and serve.