In a large pot, bring rice and 2-3/4 cups of water. Add a pinch of salt then cover and reduce heat to low. Stirring occasionally, simmer until all liquid is absorbed and rice is tender – approximately 25 minutes.

Remove pot from heat and let stand, covered, for 15 minutes.

In the meantime, prepare the mangoes, red onion, cilantro, scallions, and lemon juice.

Juice the lemon into a medium sized bowl over a sieve to collect the seeds. Add the soy sauce, olive oil, grapefruit juice, sugar, and whisk together.

In a large bowl, toss the rice, mango, onion, scallions, cilantro, sunflower seeds, and dressing until well combined.

Serve cool or at room temperature.

Garnish with fresh cilantro, lemon juice, and salt if desired.