Rinse the sushi rice under cold water until almost clear, soak in a bowl for 20 minutes, then drain.

In a pot, combine drained rice and water, cover, bring to a boil, then simmer for 8-10 minutes on low until the water is absorbed. Remove from heat and let sit covered for 10 minutes.

Transfer rice to a moistened tray. Mix vinegar, salt, and sugar, then pour over rice. Gently fold the rice to cool, covering with a damp towel.

Slice cucumber into thin strips and avocado into slices, drizzling lemon juice on avocado to prevent browning.

Rinse and drain tofu, squeezing out excess moisture. Blend tofu with vegan mayo, garlic powder, ginger, sesame oil, and a pinch of salt until smooth.

Wrap the sushi mat with cling film. Trim one-third of nori sheet and lay it rough side up on the mat. Wet your fingers and spread 150 g of sushi rice evenly over the nori.

Layer cucumber, avocado, and tofu mixture along the rice, then sprinkle with sesame seeds and panko for crunch.

Using the mat, roll tightly from the bottom to the top, sealing the edge of the nori with a little water.