Instructions

1. Rinse the rice. Place the rice in a fine-mesh strainer and rinse under cold water for a minute to get rid of some of the milky starch. Drain well.
2. Cook the rice. Place the rice and water in a medium saucepan and bring to a boil over medium-high heat. Cover and cook on low heat for 15 minutes. Remove from the heat and let steam, covered, for 15 minutes. (Alternatively, cook the rice in a rice cooker.) Meanwhile, prepare the vinegar seasoning and fillings.
3. Make the vinegar seasoning. Microwave the vinegar, sugar, and salt together in a small microwave-safe bowl in 15-second bursts, stirring between bursts, until warm to the touch and the sugar and salt are dissolved, 1 to 2 bursts. (You can also do this in a small saucepan on the stove.)
4. Prepare the crabsticks and nori sheets. Unwrap the crabsticks if needed. Halve the nori sheets: for each sheet, position it with a long side closer to you. (If the nori is scored with lines, the lines should be running from top to bottom.) Fold it in half from left to right, it should then easily tear along the crease.
5. Prepare the cucumber and avocado. Cut the cucumbers lengthwise into pencil-thin sticks (about 1/3-inch wide). Halve and pit the avocado. Peel the avocado, then cut lengthwise into 1/3-inch thick slices. For the wide center slices, lay them flat and cut into 1/3-inch wide sticks so that they are shaped like the cucumber sticks.
6. Season and cool the rice. When the rice is ready, transfer it to a large, wide bowl. Drizzle with the vinegar mixture and fold it in with a rubber spatula until thoroughly combined and cooled to room temperature. You can speed up the process by fanning it while folding.
7. Top the nori with rice. Have a small bowl of water for dampening hands handy. Place a bamboo sushi mat on a work surface with the slats running from side to side. Place a sheet of nori with a long side lined up with the bottom edge of the mat. With dampened hands, place 1/6 (scant 2/3 cup) of the rice on the nori and press into an even layer to the edges.
8. Sprinkle with sesame seeds. Sprinkle the rice with about 1/4 teaspoon sesame seeds.
9. Flip the nori and rice over and press. Flip the rice-covered nori over. Fold the top half of the bamboo mat over the nori and press down to compact the rice slightly.
10. Add the filling to the nori side. Open the mat up again. Lay 2 crabsticks across the middle of the nori. Place a row of cucumber sticks next to the crabsticks (trim them as needed to fit). Top the crabsticks with avocado slices, trimming as needed to fit.
11. Roll the sushi. Lift up the bottom edge of the mat and roll until the top and bottom of the nori are touching and the mat is completely wrapped over the sushi roll.
12. Mold the sushi. While holding the mat over the sushi roll in place, gently pull the top of the mat to pull it taut. Gently squeeze along the length of the roll so that it holds together.
13. Shape the sushi if needed. Unroll the mat. Check the sushi roll. If it is not perfectly round, fold the mat over the roll and gently shape it into a round shape.
14. Repeat rolling. Transfer the sushi to a plate seam-side down. If there is any rice stuck to the bamboo mat, remove it before making the next sushi roll. Roll the remaining pieces of nori, you may have some cucumber and avocado left.
15. Cut each roll into 6 pieces. Cut the sushi rolls with a damp knife — a very sharp chef’s knife or serrated knife works best. For each roll, cut it in half crosswise. Place the two pieces next to each other and cut twice more so that you end up with 6 pieces. Turn the pieces so that they are cut side up. For the best presentation, place the two end pieces in the middle.
16. Serve the sushi. The sushi is best served within an hour or two, so keep covered in plastic wrap to prevent it from drying out if not serving immediately. Serve with wasabi, pickled ginger, and soy sauce or tamari for dipping.