Prepare the Sushi Rice:

• Rinse the sushi rice under cold water until the water runs clear.
• Combine the rice and water in a rice cooker and cook according to the manufacturer’s instructions.
• In a small bowl, mix rice vinegar, sugar, and salt until dissolved. Once the rice is cooked, transfer it to a large bowl and gently fold in the vinegar mixture while the rice is still hot. Allow it to cool to room temperature.

Prepare the Fillings:

• Thinly slice the sashimi-grade fish, cucumber, and avocado.
• Mix mayonnaise with sriracha for spicy mayo, if desired.

Assemble the Temaki:

• Lay a half sheet of nori, shiny side down, on your palm.
• Spread a thin layer of sushi rice on the left side of the nori, leaving about 1 inch at the top for folding.
• Place your choice of fillings diagonally across the rice (e.g., a slice of fish, cucumber, avocado, and a drizzle of spicy mayo).

Roll the Temaki:

• Fold the bottom left corner of the nori over the fillings, then roll it into a cone shape. Use a grain of rice to “seal” the edge if needed.

Serve and Enjoy:

• Repeat with the remaining ingredients to make additional hand rolls.
• Serve with soy sauce, wasabi, and pickled ginger on the side. Sprinkle with sesame seeds if desired.