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

Combine rinsed rice and water in a rice cooker and cook according to your rice cooker instructions.

Once cooked, transfer rice to a large bowl, add rice vinegar, sugar, and salt, then mix gently.

In a bowl, combine drained tuna, gochujang, and sesame oil; mix well.

Prepare your vegetables by julienning cucumber and carrot.

Place a sheet of nori on a bamboo mat or flat surface, shiny side down.

Spread a thin layer of rice onto the nori, leaving about an inch at the top edge free.

Add a line of spicy tuna, followed by cucumber and carrot sticks along the center of the rice.

Using the bamboo mat, carefully roll the kimbap away from you, applying gentle pressure.

Seal the roll with a little water along the edge of the nori.

Use a sharp knife to slice the kimbap into bite-sized pieces, wiping the knife with a damp cloth as needed.

Sprinkle with sesame seeds and serve with soy sauce or pickled radish on the side if desired.