Rinse the rice. Place 3 cups of dry sushi rice in a bowl or fine-mesh strainer. Rinse gently under cold water, changing the water several times until it runs mostly clear. Drain well.
Cook the rice. Transfer the rinsed rice to a rice cooker or saucepan. Add the amount of water specified on your rice package and cook according to the package or rice cooker instructions, usually about 15-20 minutes. Follow any additional resting time required for your rice.
Season and cool. Transfer the cooked rice to a wide bowl. Let the steam escape briefly, then gently fold in 3 teaspoons of rice vinegar sushi seasoning. Taste and adjust to your preference. Let the rice cool until comfortable to handle before combining it with the salmon.
Fold in the nori. Add 1/2 cup of shredded nori to the seasoned rice. Fold gently with a rice paddle or spatula to distribute it evenly without crushing the grains.
Shape the rice balls. Lightly moisten your hands with water. Divide the rice into small, even portions and gently roll into balls. Keep them compact enough to hold together, without squeezing the rice hard.
Layer the salmon and filling. Lay a piece of food-safe plastic wrap on a clean work surface. Place a thin slice of salmon in the center. Add a small slice of avocado, a thin slice of cucumber and a little cream cheese. Keep the filling centered so it is easy to enclose.
Wrap and shape the temari. Place a rice ball on top of the filling. Gather the corners of the plastic wrap, twist them together and gently press into a round ball. Hold briefly, then carefully unwrap and place salmon-side up on a serving plate. Repeat with the remaining ingredients.
Garnish and serve. Sprinkle the salmon temari sushi with white and black sesame seeds. Serve promptly with soy sauce, sriracha or your favorite sushi sauce, drizzling lightly or serving the sauces on the side.
