Wash rice 3-5 times until clear. Bring to a boil in a medium saucepan uncovered then reduce heat to low cover and cook for 20 minutes.
Meanwhile, heat the vinegar, salt, and sugar over medium heat in a small saucepan until the sugar is dissolved.
While the rice is still warm, sprinkle the vinegar mixture over the rice, using a spoon or paddle to mix it in using slicing motions. Cover the rice with a towel to keep warm until you are ready to use it.
Make the ginger guacamole:
In a small bowl, mash the avocado, onion, spices, and lime juice with a fork until evenly mixed.
Make the sriracha mayo:
In a small bowl, stir the sriracha into the mayonnaise.
Make the sushi fillings:
Slice the cucumber, roasted red peppers, and romaine lettuce into thin strips.
Assemble the sushi burrito:
Place a sheet of seaweed shiny side down on your bamboo rolling mat. Using your fingers, cover the sheet completely with a layer of seasoned sushi rice. This is easier if you dip your fingers into water frequently.
Spoon a line of sriracha mayo about one inch from the bottom of your seaweed sheet. Place the imitation crab or fish on top of mayo. Spoon a generous layer of guacamole next to the surimi. Layer on the cucumber, roasted red peppers, and lettuce.
Start rolling the sushi by lifting the mat up and over the rice. Continue to roll, lifting the mat away from the roll as you go so it doesn’t get incorporated in the roll. When you reach the end, wrap the entire roll in the bamboo mat and give it a few good squeezes.
Place the burrito on a square piece of foil or parchment paper that is twice the length of your nori sheet. Roll once, then fold up the sides and finish rolling. Cut in half with a sharp knife.