01 - Rinse rice under cold water until water runs clear. Combine rice and water in a saucepan; bring to a boil. Cover and simmer on low heat for 10 minutes. Remove from heat and let stand covered for 10 minutes.
02 - In a small bowl, mix rice vinegar, sugar, and salt. Gently fold this mixture into the cooked rice. Allow the rice to cool slightly.
03 - Whisk together soy sauce, sesame oil, rice vinegar, sriracha, and honey in a bowl. Add tuna cubes, chopped green onions, and toasted sesame seeds. Toss gently to coat evenly. Refrigerate for 10 minutes.
04 - Combine mayonnaise, sriracha, and lime juice in a small bowl. Whisk until smooth and adjust spiciness to taste.
05 - Divide seasoned rice evenly among four bowls. Top with marinated tuna, sliced avocado, cucumber, julienned carrot, and edamame. Drizzle with sriracha mayo. Garnish with pickled ginger, nori strips, furikake (if using), and extra sesame seeds.
06 - Serve immediately, allowing guests to mix the ingredients as desired.