Prepare the Rice: Rinse sushi rice until water runs clear. Cook with water until tender. Stir in vinegar, sugar, and salt. Let it cool.
Prep the Veggies: Slice the avocado, cucumber, carrot, and bell pepper into thin strips. Keep them ready for rolling.
Assemble the Rolls: Place a nori sheet on a bamboo mat, shiny side down. Spread an even layer of rice, leaving 1 inch at the top.
Add Fillings: Arrange veggies and tofu (if using) in a horizontal line near the bottom edge of the rice.
Roll it Up: Using the bamboo mat, roll the sushi tightly while applying gentle pressure. Seal the edge with a little water.
Slice & Serve: Cut the roll into bite-sized pieces using a sharp, damp knife. Serve with soy sauce, wasabi, and pickled ginger.
