Preheat the oven to 350 degrees . In a small bowl, combine the mango, bell pepper, onion, cilantro and vinegar; season with salt and pepper.
In a shallow bowl, beat the egg with 1 teaspoon water and 1/2 teaspoon salt. Place the coconut in another shallow bowl. Dip the chicken in the egg, then in the coconut. Press to coat.
In large, ovenproof skillet, heat the oil over medium-high heat. Add the chicken and cook, turning once, until golden, about 3 minutes. Transfer the skillet to the oven and bake until cooked through, about 12 minutes. Serve the chicken with the mango salsa.