This poke bowl is super delicious and flavorful, complete with umami-soy saltiness and citrus notes. Poke should only be made with sushi-grade tuna, which you can find at specialty stores like Whole Foods or your local fishmonger. If you can’t find yellow watermelon, use cantaloupe—that ingredient’s more about color contrast. Letting the fish and fruit “marinate” really allows the flavors to meld. Make sure the sauce gets nicely pureed so it’s super smooth—in a regular blender, that means at least a minute or two. The fruit can last overnight, but the fish shouldn’t go for more than a few hours. Serve with all the accoutrements, and customize to your heart’s content.