Lightly oil the inside of a gelatin mold or line a 9-inch springform pan with plastic wrap.
Place the mangoes and lime juice in the bowl of a food processor and puree until smooth. Spread evenly over the bottom of the prepared pan and set aside.
In a large bowl, using an electric mixer, beat the heavy cream and coconut cream until soft peaks form. Refrigerate until ready to use. In a separate bowl, beat the egg whites and sugar until stiff peaks form. Gently fold the egg whites into the whipped cream until well combined. Spread evenly over the mango puree, cover, and freeze overnight.
Remove from the pan, discarding the plastic wrap, if used. Slice and serve.
(Note: Because the eggs in this recipe are not cooked, there is a risk of food-borne illness.)