For the Sushi Rice:
2¼ cups sushi-grade rice
2¼ cups water
5 tablespoons unseasoned rice vinegar
1½ teaspoons sea salt
2 tablespoons granulated sugar
For the California Rolls:
1½ cups crabmeat (7 ounces) or 7 sticks faux crabmeat
Fourteen ½-inch-square, 4-inch-long cucumber sticks
½ pitted large avocado, cut into 14 long sticks and peeled
Toasted white sesame seeds, to garnish
7 half-sheets nori
6 cups prepared sushi rice (the entire yield from the recipe above)
1. Make the Sushi Rice: Pour the rice into a fine-mesh strainer, large enough so you can freely toss and turn the grains. Have at hand a larger bowl into which the strainer can easily fit and fill it with cold tap water. Pour the rice into the strainer, then lower the strainer into the large bowl so that the water covers the rice. With both hands, gently rub, turn, and toss the rice. Do not press the grains too hard against the strainer or against one another, or the fragile grains may break. The water will instantly turn milky white, so remove the strainer from the large bowl, discard the water, and refill the bowl with fresh cold water. Return the rice-filled strainer to the bowl and repeat. On the second rinsing, the water will look only slightly milky. Repeat twice more. When you have finished, the water will be almost clear, but it will not reach 100% clarity. Drain the rice and let it sit in the strainer for 10 minutes.
2. Transfer the rice to a heavy-bottomed pot that is deeper than it is wide and has a heavy, tightly fitting lid, add the water, and let it sit for 20 minutes.
3. Set the rice over medium heat and cook, uncovered, until the water has nearly absorbed the rice, about 10 minutes. Quickly reduce the heat to very low, cover the pot with the lid, and cook until the rice is plump and cooked through, another 10 minutes. The rice should now be completely transparent. If you see any dry, very white-looking grains, sprinkle a little warm water over the dry spots and cook another couple of minutes or so over very low heat. During the cooking, never stir the rice.
4. After confirming that all the rice grains are transparent, immediately put the lid back on before the built-up steam can escape. Turn off the heat and let the rice stand for 5 minutes.
5. While the rice is cooking, put the rice vinegar, salt, and sugar in a bowl and stir with a whisk until the sugar and salt are almost dissolved.
6. If you are using a wooden sushi tub and wooden paddle, soak them in a bath of cold water for half an hour while the rice is cooking. Drain the water and wipe the tub and paddle with a dry kitchen towel. Other bowls made of metal, glass, or porcelain can be substituted.
7. Transfer the steaming hot cooked rice all at once to the bowl. Quickly and gently break up the rice, crisscrossing it with the side of your paddle. Pour the prepared vinegar dressing evenly over it and, with the paddle; break up the lumpy clumps and turn the rice over, working one area at a time. Repeat once or twice until you can tell by looking that the vinegar dressing is roughly distributed throughout the rice.
8. Push the rice toward one side of the tub. Hold the paddle horizontally and rapidly move it back and forth with many small strokes. Work on the remaining areas of the rice one at a time in the same way, until you have moved all of the rice to the other side of the tub. Rotate the tub or bowl 180 degrees and repeat the process. The whole procedure should take about 2 minutes.
9. With a hand fan or with a magazine or folded newspaper, fan the rice for about 30 seconds. Let the sushi rice cool to a temperature of 104 degrees F before using, covered with a moist kitchen cloth to prevent it from drying out.
10. Make the California Rolls: Line up all the filling ingredients (crabmeat, cucumber, avocado, and sesame seeds) on a tray along with the sushi rice and half-sheets of nori, stacked up in a closed sealable plastic bag. Have at hand a small bowl containing 1 cup of cold water with 2 tablespoons of rice vinegar for moistening your hands and a moistened clean cloth. Open up your bamboo rolling mat and wrap it tightly in plastic wrap. Have a well-sharpened cutting knife at hand.
11. Place one half-sheet of nori, shiny side down, on the rolling mat with a long side facing you. Moisten your hands slightly with the vinegar water and pick up the sushi rice (a little less than a cup - about the size of a baseball), forming into a roughly egg-shaped ball without squeezing. Place the rice ball on the nori, ½ inch from the upper far left edge of the nori. Spread the rice evenly to the right, leaving ½ inch of the far end of the upper end of the nori uncovered. Using your fingers, spread the rice towards you, until you have covered the whole area (except for the ½ inch at the top). Sprinkle the surface of the rice evenly with 1 tablespoon of white sesame seeds to form an outer coating for the roll.
12. Flip the rice-covered nori sheet over onto the rolling mat, lining up the bottom edge of the mat and the nori sheet evenly. The nori is now on top of the rice. Arrange the crabmeat across the nori from left to right, one-quarter of the way up the side nearer you. Place two sticks of cucumber over the crabmeat and then two sticks of avocado on top of the cucumber sticks.
13. To roll, lift up the bamboo mat near you and fold it over the fillings. As you roll and the bamboo mat reaches to the surface of the nori, pull back the edge of the bamboo mat (so that you do not roll it into the sushi) and continue to roll tightly until the whole roll is completed, leaving the seam down the roll. Now place the bamboo mat over the roll, hold it securely to firm it up, and square of the edges slightly. Unroll the rolling mat.
14. To cut the roll into six equal pieces, first cut across the center with a sawing motion, not pushing down too hard, then cut each half-roll into thirds, wiping the blade of the knife with the moist cloth to remove the rice residue when necessary.
Serve the rolls with a spicy mayonnaise, soy sauce, or wasabi. You can prepare this roll several hours in advance. For short-term storage, wrap each uncut roll in plastic wrap, put it in a sealable container, and store it in a cool, dry, dark place. Or for longer-term storage, refrigerate it in the vegetable bin.