In a large bowl, combine the garlic with a pinch of salt and 1 tablespoon of the olive oil and let stand for 5 minutes. Add the onion, lime zest and the remaining 2 tablespoons of olive oil and let stand for 5 minutes. Add the lime juice, pineapple, tomatillos, tomato, red and green bell pepper and the serrano and mix well. Season with salt.
Season the mahi mahi with salt. Put the eggs and plantain chips in separated shallow bowls. Dip the fish in the egg, letting excess drip off. Dredge the fish in the chips to coat well.
In 2 large skillets, heat 1/4 inch of vegetable oil. Add half of the fish to each skillet. Cook over medium high heat for 1 minute. Turn the heat down to medium and cook until browned and crisp, about 3 minutes. Turn the fish and cook about 3 or 4 minutes longer. Serve the fish with the salsa.