Peel and finely dice the mangoes. Finely dice sweet onion and red sweet pepper. Finely chop scallions and cilantro. Mix well in a bowl and squeeze the juice of two key limes into the bowl. Add a pinch of salt and coarse pepper for a bit of kick. Can be served immediately but is better if kept in the refridgerator to marinade at least 4 hours. This recipe can be spiced up with some jalapenos.