Pre-heat oven to 180oC (160oC fan-forced). Grease and line 3 x 20cm shallow cake pans.
Place flour, sugar, coconut and cinnamon in a large mixing bowl. Mix well.
Whisk together the oil and eggs. Add banana and pineapple, mixing well. Pour into dry ingredients and mix to combine.
Spoon batter evenly between prepared tins and bake for 16-18 minutes, or until an inserted skewer comes out clean. Cool in tins for 10 minutes before removing to a cooling rack to cool completely.
Beat together cream cheese and butter in a large mixing bowl. Add icing sugar gradually until all combined and smooth. Spread or pipe icing over the top of each cooled cake and stack on top of each other. Sprinkle with walnuts and coconut.