Rinse sushi rice under cold water until it runs clear. Combine with water in a saucepan, bring to boil, reduce heat, cover, and simmer until tender.

Mix rice vinegar, sugar, and salt in a small bowl until dissolved. Fold this into the cooked rice with a wooden spatula.

Slice cucumber into matchsticks and dice avocado into cubes while rice cools.

In serving bowls, layer sushi rice, then top with cucumber, avocado, and crab in a visually appealing manner.

Drizzle soy sauce and sriracha over the assembled bowls, adjusting spice level as desired.

Serve immediately and enjoy the fresh flavors and textures.