Prepare the sushi rice by rinsing it thoroughly.
Cook the rice in water.
Combine rice vinegar, sugar, and salt in a bowl until dissolved.
Fold the vinegar mixture into the cooked rice, being careful not to mash it.
Preheat the oven to 375°F (190°C).
Prepare the spicy salmon mixture by combining diced salmon, mayonnaise, sriracha, and soy sauce.
Spread the seasoned sushi rice evenly in a baking dish.
Top the rice with the spicy salmon mixture and spread evenly.
Sprinkle panko breadcrumbs on top to create a crispy crust.
Bake in the preheated oven for 20-25 minutes until the top is golden and crispy.
Remove from the oven and let cool for a few minutes.
Garnish with avocado slices and green onions before serving.