Make some sushi rice according to package instructions. Once done, sprinkle in one to 2 tablespoons of rice vinegar, stir, and refrigerate until cold.
Dice up some fresh salmon (make sure the skin is removed) and toss the cubes in the sauce sauce.
Cut seaweed paper into fourths. Spoon about a tablespoon of rice into the center and push down into a cupcake tin. Scoop another tablespoon of the salmon mixture on top of the rice and repeat until the cupcake tin is full.
Bake at 450°F for 6-8 minutes, until the salmon has a nice crisp on the edges. Removed from the oven and let cool for 10 minutes.
Play your sushi cups, and top with additional kewpie, mayo, sriracha, green onions, and sesame seeds.