Rinse the rice under cold water until the water becomes clear. Drain well.

Place rice and 1 ½ cups water in a medium saucepan over high heat. Bring to the boil. Then, reduce the heat to low and bring it to a simmer. Gently stir the rice. Cover the rice and simmer for 15 minutes. Remove from heat and then allow to rest for 15 minutes covered.

Transfer the cooked rice to a glass bowl. Break up the rice using a wooden spoon and gently mix through the vinegar, sugar, and salt.

Line a 22 x 13cm (8.66 inches x 5.12 inches) baking dish with parchment paper.

Place sushi rice evenly in prepared baking dish, pressing down to compress the rice, and place in fridge, covered, for 1 to 2 hours or until firm.

Once the rice is firm, remove the rice from the baking dish and cut into small squares or rectangles.

Heat oil in a medium sized frying pan. Once hot, fry each rice square until lightly golden brown on one side, then turn and cook the other side until lightly golden brown. Allow the rice to rest on a cooling rack once cooked. Set aside.

In a medium sized mixing bowl combine the tuna, mayonnaise, Sriracha, and salt and pepper.

Cover and place in fridge for 30 minutes (optional).

Place a spoonful of tuna mixture on top of a piece of fried rice. Repeat until all ingredients are used up.

Garnish with toppings of your choice if desired.