California Rolls

In saucepan, bring water and rice to boil; reduce heat to low, cover and cook for 25 minutes or until tender.With fork, toss with vinegar, sesame seeds and salt ; let cool completely. Meanwhile, using scissors, cut nori in half crosswise to make six 7- x 4-inch (18 x 10 cm) rectangles.

For each roll, place rolling mat on work surface with longest side closest. Cut plastic wrap same size as mat and place on mat; brush lightly with vegetable oil. With wet fingers, press rounded 1/2 cup (125 mL) rice over wrap into same-size rectangle as nori, leaving 1 inch (2.5 cm) border at closest edge. Place nori sheet on rice.

Filling:
Stir wasabi powder with 2 teaspoons (10 mL) water; spread 1/4 teaspoon (1 mL) into thin line about 1/2 inch (1 cm) from closest edge. Top with one-sixth of the cucumber, then crab; arrange one-sixth of the avocado in row beside. Holding filling in place with fingers and using mat and plastic wrap as support, bring mat over filling.

Roll up tightly, lifting closest end of mat as you roll. Squeeze to compress. With sharp wet serrated knife, trim ends; cut roll into thirds. Slice each into 2 diagonal pieces. Place flat side down on serving plate. Top each with fish roe, if using.