- Core, rinse and drain lettuce; refrigerate in plastic bag.
- Combine rice and 2 cups water in medium saucepan; bring to boil. Reduce heat, cover and simmer 20 minutes, or until water is absorbed. Remove from heat and let stand 20 minutes, covered.
- Meanwhile, combine vinegar, sugar and salt in small saucepan; heat only until sugar dissolves, stirring constantly.
- Turn cooked rice out into large non-metal bowl, separating kernels with fork. Pour vinegar mixture, a little at a time, evenly over rice; gently folding to combine after each addition. Cool rice mixture to room temperature.
- Cut lettuce in half lengthwise. Carefully separate leaves.
- Cut or shred crabmeat into bite-size strips.
- Just before serving, cut each avocado in half; seed and peel. Cut each half lengthwise into 8 thin slices. Arrange avocado slices, lettuce leaves and crabmeat on large platter.
- Fluff rice mixture with fork.
- To make Temaki-Zushi: Place lettuce leaf in palm of hand. Spread 1 to 2 Tbsp. rice mixture in center of lettuce. Top with avocado slice and one piece crabmeat. Wrap lettuce around filling in cone shape to enclose. Serve with soy sauce.