Quickly whisk rice vinegar, sugar, and salt until dissolved completely. Pour over cooked sushi rice, and mix until incorporated.
Spicy Mayo:
Whisk together mayo and sriracha until incorporated. Transfer to a squeeze bottle or a small plastic bag and snip a tiny hole in the corner.
To assemble:
Divide rice into two bowls, warm or cold, it's up to you. Warm tastes great in bowl format, but you can eat the rice cold like a sushi roll. Add one half of avocado (sliced) to each bowl and drizzle spicy mayo on top.
Top with nori strips and sesame seeds.
Serve with soy sauce. Enjoy!
Notes
*Regular rice works too. I initially made this because I planned on rolling actual rolls, but then I got lazy and was more concerned about eating than making it pretty.