Preheat oven to 425 degrees Fahrenheit.
To make the rice, mix the rice, coconut milk, and 3/4 cup of water in a rice cooker and cook until done. Alternatively, cook the mixture on the stove following the rice package directions.
In a glass bowl or measuring cup microwave 2 tablespoons water for 2 minutes. Add white miso paste and mix with a fork until dissolved. Add brown sugar and soy sauce and mix until smooth.
Put a large piece of foil on a baking sheet and place the salmon fillets in the center, skin side down. Fold the edges of the foil around the salmon to form a bowl, make sure the corners are sealed.
Pour the miso mixture over the salmon and bake for 12-24 minutes until flaky (bake time will depend on the thickness of your fillets).
Plate the rice, place the salmon on top, and drizzle any extra miso glaze over the salmon.