Preheat the oven to 350 degrees. Stir together the graham cracker crumbs, shredded coconut, and melted butter until the mixture holds together when pressed.
Press the crust mixture firmly into the bottom of an 8x8 baking pan. Bake for 10 minutes, then let it cool completely.
Whisk the sweetened condensed milk, key lime juice, and coconut cream in a bowl until smooth. Pour this filling over the cooled crust.
Chill the pan in the refrigerator for at least 4 hours until the filling is firm.
Whip the heavy cream with the powdered sugar until soft peaks form. Spread the whipped cream over the chilled filling.
Sprinkle the toasted coconut flakes and key lime zest evenly across the top before slicing into bars.