Onigiri is the ideal celebratory springtime snack: It’s filling yet light, thanks to the vinegared sushi rice, and can be prepared in advance and served or eaten whenever the mood strikes.
Preheat oven to 375°F.
While the oven is heating, cook your rice by your preferred method, whether it be a rice cooker or on the stove top.
In a small saucepan, heat the sushi rice seasoning ingredients until the sugar and salt dissolve, then set aside to cool. This is more seasoning than you will need but this will keep in your fridge until you make your next batch of sushi rice.
Place the salmon on a baking sheet lined with parchment paper or aluminum foil, then bake until the center is opaque, about 10–15 minutes, depending on the thickness of your fish. When the fish has fully cooked, remove from oven and season with a pinch of salt.
When the rice is cooked, transfer to a mixing bowl and quickly add 3 tablespoons of your prepared sushi seasoning.
Fold the seasoning in without breaking up your rice grains. If you have an extra hand, have someone fan the steaming rice for you while you stir—this makes the rice shiny and appetizing looking.
When the salmon is just slightly cooled, break up with a fork and gently mix in with the rice.
Using either an onigiri press or your own hands, shape the rice into the desired shape (traditionally either a triangle or a ball), occasionally wetting your hands with water to make the rice more manageable. The key is to compress the rice enough so it won’t fall apart—but not so much that you’re smashing the kernels.
Garnish with pickles or edible flowers and serve with ponzu or soy sauce.