Rinse 1 cup of sushi rice under cold water in a fine-mesh strainer until the water runs clear. Cook the rice with 1.5 cups of water in a rice cooker or medium saucepan. Bring to a boil, then cover and reduce heat to low, simmering for 18–20 minutes. Once cooked, let it rest for 10 minutes off the heat.

Transfer the warm sushi rice to a large bowl and gently fold in 3 tablespoons of rice vinegar, 2 tablespoons of sugar, and 1 teaspoon of salt. Use a spatula to mix without smashing the grains. Allow the seasoned rice to cool to room temperature for assembly.

Finely slice half a cucumber to create ribbons or matchsticks. Cut one ripe avocado in half, remove the pit, and scoop the flesh out, then cube it into bite-sized pieces. Set the chopped cucumber and avocado aside.

Scoop a generous portion of the cooled sushi rice into individual serving bowls as the base. Arrange the cucumber slices and avocado chunks on top, sprinkling them evenly for presentation. Add shredded imitation crab meat or your protein of choice.

In a small bowl, mix together soy sauce and sriracha for a spicy kick. Drizzle this mixture over each assembled bowl.

Serve the assembled California Roll Sushi Bowls to family or guests, ensuring they are served fresh.