Add the rice and water to a rice cooker and cook.
Spread the cooked rice on a baking sheet and let it cool to room temperature.
While the rice cooks, prepare the ingredients.
Combine the cooled rice with the prepared ingredients in a large bowl.
In a small bowl, mix the Mirin, vegetable oil, toasted sesame oil, rice vinegar, sugar, and salt. Drizzle over the cold rice and mix. Taste and add more salt if necessary. Cover and refrigerate until ready to use.
Cut the pineapple in half vertically with a large knife. Try to keep the leaves and top neat and intact if you are going to use it for a bowl.
Use a smaller knife to cut a grid into the pineapple. Pull the edges a little to loosen the pineapple. Use a spoon to scoop out the pineapple. You’ll have to scrape and sometimes use the knife to break the pineapple free.
Set aside the pineapple halves to use as bowls.