Whisk together the olive oil, soy sauce, lemon juice, garlic, red pepper flakes, black pepper, ginger, green onion, and salt in a bowl. Add the mahi-mahi and toss to evenly coat. Cover and marinate in the refrigerator for 1 hour.

Prepare Coconut Rice. This can be made stovetop or in a rice cooker.

Rinse rice thoroughly.

Rice Cooker - Add broth, butter, rice, cook until liquid has almost all absorbed, then add in coconut milk and sugar, stir and let continue cooking.

Stovetop - Bring the rice, broth, and butter to a boil in a saucepan over high heat. Reduce heat to medium-low, cover, and simmer until the liquid has been absorbed, about 20 minutes. Pour in the coconut milk and sugar. Stir, and simmer uncovered until the rice has absorbed most of the coconut milk.

Preheat the oven on broil low, and set the oven rack in the middle of the oven. I recommend using a cast iron pan or sheet and allow to heat up while the oven preheats.

While the rice is cooking, remove the mahi-mahi from the marinade, and shake off excess. Discard the remaining marinade.

Place fish in the preheated pan in a single layer, skin side down. Broil until the fish flakes easily with a fork, 10 to 15 minutes. If the fish browns too quickly, cover with a sheet of aluminum foil.

Melt butter and sugar in a skillet over medium-high heat. When the mixture begins to bubble, stir in sweet red peppers, cook for 1-2 minutes then add mango. Cook and stir until mango is tender about 5 -minutes.

Serve fish over coconut rice topped with mango salsa.