Prepare the Sushi Rice:
Rinse the sushi rice under cold water until the water runs clear.
Cook the rice according to the package instructions. Once done, let it cool slightly.
Mix the rice vinegar, sugar, and salt in a small bowl. Gently fold this mixture into the cooked rice, ensuring it’s evenly coated. Set aside to cool completely.
Prepare the Filling:
Peel and slice the avocado into thin strips.
Cut the cucumber into thin matchstick-like pieces.
Assemble the Roll:
Lay a sheet of nori, shiny side down, on the bamboo mat covered with plastic wrap.
Wet your hands with the water-vinegar mixture to prevent sticking. Spread a thin, even layer of sushi rice over the nori, leaving about 1 inch of space at the top edge.
Place a few slices of avocado and cucumber horizontally about 1 inch from the bottom edge of the rice.
Roll the Sushi:
Use the bamboo mat to gently roll the sushi, starting from the edge closest to you. Roll tightly, pressing as you go to form a firm roll. Seal the edge with a bit of water.
Slice the Roll:
Use a sharp knife to cut the roll into 6-8 equal pieces. Wipe the knife with a damp cloth between cuts to keep it clean.
Serve:
Arrange the sushi rolls on a plate. Serve with soy sauce, pickled ginger, and wasabi on the side.