To make the Avocado Crema: Pulse the avocado, 1 tablespoon lime juice, and some of the crema together in a blender. Add more lime juice to taste or to help get the blade running. Stir the mixture with a rubber spatula between pulses to get it to blend. Transfer the mixture to a small bowl and whisk vigorously with the remaining crema to eliminate any remaining lumps. Store covered in the refrigerator until ready to use.
To make the the Chayote Slaw: Thinly julienne the mirliton and carrot on a French mandoline. Add to a small bowl along with the cilantro and garlic. Right before serving, toss the slaw with the lime juice and salt.
To make the Coconut Rice: Combine 1 1/2 cups of the coconut milk with the Coca-Cola in a liquid measure and set aside. Add the remaining 3 cups of the coconut milk to a 4-quart heavy bottom pot set over medium-high heat. Bring to a boil, reduce to medium, and simmer, stirring as needed with a wooden spoon until reduced, about 30 minutes.
Continue cooking until the coconut milk breaks, and the oil in the milk solids separates, another 15 minutes or so, stirring more frequently. Light golden bits will begin adhering to the bottom and sides of the pot.
Scrape them up with the spoon and continue doing so until there is clear coconut oil and lots of little brown bits. Add the rice to the pot and toss in the coconut oil. Add the salt and continue stirring until the rice is translucent, about 2 minutes.
Add the coconut milk and Coca-Cola mixture to the pot and bring to a boil. Reduce heat to a simmer and continue to cook the rice until the liquid is reduced and rice begins to appear at the surface, about 15 minutes. Cover tightly, reduce heat to low, and continue to cook 15 minutes longer. Turn off the heat and allow the rice to stand 5 minutes before fluffing with a fork. Add the green onion and cook until heated through.
Add 2 tablespoons of canola oil to a 12-inch sauté pan and heat over medium high heat. Add the crabmeat and sauté until warmed through. Mix in with rice. Taste for seasoning and add salt as needed. Set aside.
To make the red snapper: Combine the rice flour and corn flour in a shallow container. Add the coriander, cumin, paprika, cayenne, the 1 tablespoon salt and pepper. Mix to combine. Lightly season the fish fillets with salt, then dredge in the flour mixture and set aside.
Meanwhile, add enough canola oil in another 12-inch sauté pan set over medium-high heat to come 1/3 of the way up the sides of the fish. Once the oil is hot, add the fillets and cook until nicely browned and cooked through, about 2 to 3 minutes on each side. Transfer to a paper towel line plate to drain briefly before serving.
To make the plantains: Add enough oil to a 12-inch sauté pan to come 1/3 of the way up the sides of the plantains and heat over medium. Add the plantains to the hot oil and cook until tender and golden on both sides, about 5 minutes. Using a slotted spoon, transfer the plantains to a paper towel lined plate to drain and season lightly with salt.
To serve: divide the coconut rice among four plates. Divide the plantains and crab among the four plates and arrange next to the rice. Place the fish fillets on top of the rice. Drizzle about 2 tablespoons of the avocado crema over each fillet, and top with the mirliton slaw. Add a cilantro sprig to each for garnish.