Preheat the oven to 375°F (190°C).

Rinse sushi rice under cold water until the water runs clear, then cook it with water in a medium saucepan until tender.

In a small bowl, mix rice vinegar, sugar, and salt until dissolved, then fold into the cooked rice.

In a large bowl, combine fresh salmon, mayonnaise, sriracha, sesame oil, and green onions until well mixed.

Spread the seasoned rice in a greased baking dish, then layer the salmon mixture evenly on top.

Bake in the preheated oven for 25-30 minutes until golden brown and cooked through.

Remove from oven, cool briefly, then garnish with green onions, nori strips, and optional tobiko before serving.