• Place the short grain rice in a fine mesh strainer and rinse until the water that runs out of the bottom is clear. This gets some of the starch out of the rice. In a medium saucepan, combine the rice with 2½ cups (591g) of water, cover and cook on low heat for 20 minutes. Remove from the heat and fluff the rice with a fork. In a small bowl stir together the rice vinegar, sugar and salt. Add to the rice and fluff once more. Keep warm until ready to serve.
• Place the sheets of nori on a clean, dry work surface. Working one at a time, spread about 3 tablespoons (47g) of the rice onto the right edge of the sheet of nori. Wet your fingers and press the rice to spread it into an even square over the right half of the sheet.
• Spread a spoonful of the fish of choice over the rice and top with any desired toppings (a few pieces of avocado, cucumber, green onion or sesame seeds - all optional).

For rolling into a cone shape:

• If rolling into a cone shape, arrange the toppings on the diagonal facing the right top corner. Roll the bottom right corner and fold it to the center, then continue rolling to the left until it forms a cone shape. Serve immediately with soy sauce or ponzu for dipping.

For rolling into a cylinder:

• If rolling into a cylinder, arrange the toppings in the middle, facing directly up and down. Roll up as you would a cinnamon roll. Serve immediately with soy sauce or ponzu for dipping.