First cook your rice, either in a rice cooker or on the stove. If making it on the stove, bring the rice and water to a boil, then reduce heat and simmer for 15 minutes, then steam for 10 minutes. While this is cooking, add your rice vinegar, sugar and salt to a small saucepan and heat on very low heat until sugar and salt are melted. When your rice is done, fold in the vinegar mixture until well combined.
To make the crab salad, first shred the imitation crab chunks using two forks, like you would shred chicken. Then combine the Japanese mayo, shredded imitation crab, sriracha, soy sauce and salt.
Top the sushi bowl with 2 small carrots, 1/2 cucumber, 1/2 avocado, 1/4 cup edamame and then garnish with scallions and yum yum sauce.