Place the rice in a sieve and set the sieve in a bowl. Add water, then gently rub the rice between your hands. The water should become milky. Discard the water. Repeat until the water becomes relatively clear. Drain the rice for 30 minutes.
Transfer the rice to a heatproof bowl (preferably metal as ceramic may crack over time) that can be fitted in a pot. Add the 185ml of water and set aside to let the rice soak for at least 30 minutes.
Fill the pot with a bit of water, about 1/2 to 3/4-inch tall. Place the bowl of rice inside. Cover the pot with a lid and turn on the heat to high. Once the water in the pot (not in the rice) has come to a boil, reduce the heat to low and simmer for 15 to 20 minutes until all the water has been absorbed. Try not to open the pot cover while the rice is simmering.
After all the water has been absorbed, turn off the heat and let the rice steam in residual heat for 10 minutes.
Rice Vinegar Sauce
Combine rice vinegar, sugar and salt in and large small pot or small bowl. Heat up / microwave until the sugar has dissolved.
Tuna Filling
Rinse and dry the cucumber. Cut into long strips. Set them aside.
Tip the canned tuna into a sieve and drain well. Using a spoon, press down onto the tuna to get rid of excess water.
Transfer the tuna into a bowl and flake the tuna into small pieces. Add in mayonnaise and wasabi and stir to mix them together. Taste and see if you want to add in more wasabi.
Back to Sushi Rice Again
You will have to work quickly for the next few steps. Get ready a fan (electric or manual), a spatula and a large mixing bowl with and dust wide surface area.
Place the mixing bowl on top of a damp bowl to prevent it from sliding. Tip the still-hot sushi rice into a large mixing bowl.
Drizzle in the Rice Vinegar Sauce then using the spatula, gently combine the rice and vinegar using a cutting motion with the edge of the spatula, while fanning the rice using another hand. (See video here.) It's easier if you have someone helping you to fan the rice while you mixing the rice.
When all the vinegar has been absorbed, the rice should have cooled down considerably. The rice should be a bit warm but not hot, continue mixing and fanning if the rice is still hot.
Once the rice has cooled down, cover with and damp tea towel and get ready to roll!
Making the Sushi Rolls
If desired, toast the nori on a non-stick frying pan over medium heat until warmed through.
Place the nori on a bamboo rolling mat, rough side up.
Spread half the rice on the nori, leaving some spacing at the top. Spread the Tuna Filling in the middle of the rice, then top with a few strips of cucumber. (See step-by-step photos for illustration.)
With the help of the bamboo mat, roll up the sushi tightly, making sure the start of the rice meets the end of the rice to make a nicer looking roll.
Stick a few pieces of rice on to the end of the nori (to help sticking) then roll it up. Use the bamboo mat to help to keep the roll tight - but don't squash it too hard until it goes out of shape.
Repeat to make the second roll.
Cut the rolls into 6 pieces each, wiping the knife with a damp cloth after before each slice. Serve immediately.
NOTES
- It may not be easy to roll the sushi roll tightly at the start, just keep practicing!- You can make mini sushi rolls also, just cut the nori into half and proceed. However, make sure you spread a thinner layer of rice otherwise you will have problem rolling it up.- Sushi rice recipe adapted from No Recipes