1. Mix cooked rice with rice wine and vinegar and set aside.
2. Lay down bamboo mat so slats run horizontally.
3. Place 1 sheet of nori on top, making sure lines run vertical.
4. Spread sesame seeds on the nori; top evenly with rice.
5. Place 2 sticks of crabmeat, 2 slices of avocado and a bit of cucumber along the center of the rice.
6. Fold up mat from both ends to the center, and with two hands roll while pressing firmly to create two rolls.
7. Remove the mat and wrap each roll with plastic wrap until ready to serve.
8. When serving, dip a sharp knife in warm water and slice through plastic to create bite-size pieces. Remove the plastic before serving.
9. Serve the rolls with soy sauce, wasabi and ginger.
Sushi rice is extra-sticky.