Mix cake according to manufacturer’s instructions. Deposit 1.5 pounds into a sprayed and papered 8-inch pan. Repeat 2 times to make 3 cakes total. Bake at 350°F until cake springs back lightly when touched. Let cool completely and depan. Once cooled, trim the bellies of each cake, saving them for other uses. Pipe buttercreme around the edges of one cake round. Using a #8 gray scoop, place one scoop pineapple filling on the cake round and spread to edges and place another cake round on top. Repeat with the next layer. Crumb coat with buttercreme, smooth ice, then gently dab cake all over with coconut. Decorate with fresh flowers.