Preheat your oven to 375°F (190°C).

Rinse the sushi rice under cold water until the water runs clear. Combine the rinsed rice and water in a rice cooker or pot, and cook according to the rice cooker instructions or bring to a boil, then reduce heat to low, cover, and simmer for 20 minutes.

In a small bowl, mix the 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. Allow the rice to cool slightly.

While the rice is cooling, prepare the salmon. Place the salmon fillet in a baking dish and bake for 15-20 minutes, or until cooked through. Remove from the oven and let it cool slightly, then flake the salmon with a fork.

In a separate bowl, mix the flaked salmon with mayonnaise, sriracha sauce, and sesame oil until well combined.

In a large baking dish, spread the sushi rice evenly across the bottom. Layer the spicy salmon mixture on top of the rice.

Bake in the preheated oven for 10-15 minutes, until heated through and slightly crispy on top.

Remove from the oven and top with sliced avocado and chopped green onions. Serve with nori strips and soy sauce on the side.