01 - Rinse sushi rice under cold water until water runs clear. Combine with water in a saucepan, bring to a boil, then 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 and allow it 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, then refrigerate for 10 minutes.
04 - Combine mayonnaise, sriracha, and lime juice in a small bowl. Mix until smooth and adjust spiciness to taste.
05 - Divide seasoned sushi rice evenly among four bowls. Arrange marinated tuna, avocado slices, cucumber, julienned carrot, and edamame on top. Drizzle with sriracha mayo. Garnish with pickled ginger, nori strips, optional furikake, and extra sesame seeds.
06 - Serve immediately, allowing diners to mix ingredients as desired.