Prepare the Sushi Rice:

Rinse the sushi rice in cold water until the water runs clear.

Cook rice according to package instructions or in a rice cooker.

Transfer cooked rice to a bowl, mix in rice vinegar and sugar, then set aside to cool.

Make the Teriyaki Chicken:

In a bowl, combine sliced chicken with mirin, soy sauce, sugar, garlic, and ginger.

Heat olive oil in a pan over medium heat.

Sauté chicken until browned and cooked through, stirring occasionally. Be careful not to burn the sauce.

Remove from heat and allow to cool.

Assemble the Sushi Rolls:

Place a sheet of nori (shiny side down) on a bamboo sushi mat.

With wet fingers, spread a thin, even layer of sushi rice over the nori, leaving a 1-inch border at the top.

Arrange chicken and cucumber strips horizontally over the rice.

Drizzle 1–2 lines of Japanese mayonnaise on top.

Carefully roll up the sushi using the bamboo mat, applying gentle pressure.

Moisten the top edge with water to seal the roll.

Slice into 8 equal pieces with a sharp knife.

Serve:

Arrange on a plate and serve with soy sauce and extra mayo on the side.

Best enjoyed fresh or chilled for 1–2 hours before serving.