Cook sushi rice according to package instructions. Once cooked, let it cool and chill in the refrigerator.

Dice the watermelon, cucumber, and slice the avocado and radishes. Chop the green onions.

In a small bowl, whisk together soy sauce, sesame oil, rice vinegar, honey, and sriracha until well combined.

In serving bowls, place a scoop of chilled sushi rice. Top with diced watermelon, cucumber, avocado, radishes, and green onions. Drizzle with dressing and sprinkle with sesame seeds.