Combine rice and water and cook until the rice is fluffy and the water is absorbed. I like to use my rice cooker.
Whisk together the rice vinegar, sugar and salt until the grains are mostly dissolved. Transfer the rice to a glass or non-reactive bowl and toss it with the vinegar mixture.
Mix together the mayo and sriracha.
Layer three bowls with the rice mixture, diced cucumber, diced avocado, and flaked smoked trout. Drizzle with the sriracha mayo and sprinkle with the noir sheet pieces and sesame seeds.
Recipe by Alisons Allspice at https://www.alisonsallspice.com/smoked-trout-sushi-bowls/