Rinse sushi rice under cold water until it runs clear. In a pot, combine rice with water and salt. Bring to a boil, reduce heat, cover, and simmer for 15 minutes. Let sit for 10 minutes.

Heat olive oil in a skillet over medium-high heat. Cook shrimp for 2-3 minutes per side until opaque. Mix with soy sauce, rice vinegar, sesame oil, sugar, and sriracha.

In a small bowl, combine mayonnaise and sriracha, whisking until smooth. Adjust spice level to taste.

Prepare a mold and layer sushi rice first, then shrimp, avocado, and cucumber. Repeat layers to desired height.

Remove the mold and garnish with sesame seeds and herbs. Drizzle with spicy mayo and serve immediately.