Season the cooked sushi rice with rice vinegar and let it cool.
Place a sheet of nori shiny-side down on a bamboo sushi mat.
Spread an even layer of sushi rice over the nori, leaving a 1-inch border at the top.
Arrange tempura shrimp, cucumber, avocado, and carrot across the center.
Drizzle with Japanese mayonnaise and sriracha if using.
Roll the sushi tightly using the bamboo mat.
Seal the edge with a little water.
Slice each roll into 8 equal pieces using a sharp wet knife.
Sprinkle with sesame seeds.
Serve immediately with soy sauce, pickled ginger, and wasabi.
