Add the vanilla and rum and cook for a further 5 minutes to glaze. Cool and spoon onto the coconut cream pie. Sprinkle over the lime zest and extra coconut to serve.

Pour mixture into frozen pie shell. Bake in preheated oven until filling is set, about 50 minutes. Meanwhile, stir together oats, pecans, coconut, remaining 2 tablespoons brown sugar, remaining 2 ...