Preheat your oven to 170C / 340F (fan off), 150C / 300F (fan on). Spray the bottom and side of a 22 x 33 x 5cm / 9 x 13 x 2.25-inch cake tin with oil spray and line with baking paper.

Carrot - Grate the carrots using a regular grater and set aside.

Combine dry ingredients - Add the all-purpose flour, baking powder, bicarb soda, salt, cinnamon, and shredded coconut to a medium sized mixing bowl and use a whisk to combine. Set aside.

Mix oil, sugar and eggs - To a separate bowl, add the oil and brown sugar. Mix until well combined. Then add the eggs one at a time, mix well each time.

Add dry ingredients - Add the dry ingredients and use a spatula to mix until well combined.

Finish batter - Next, add the walnuts, grated carrots, coconut, orange zest and orange juice and mix until well combined. The mixture will seem thick at first but as you mix it will thin out.

Bake - Pour the batter into your cake tin and spread out. Bake for 20 minutes or until a toothpick inserted into the center comes out clean.

Beat butter and cream cheese - Add the cream cheese and butter into a large mixing bowl. If you have a stand mixer, use the paddle attachment. Mix on medium speed until the mixture is well combined and creamy, about 4-5 minutes.

Finish frosting - Add the vanilla extract, powdered sugar and milk powder and mix on low speed to begin with. Then turn up to high speed when there are no dry ingredients showing. Continue beating on high speed until pale and creamy, about 5 minutes. It will be smooth, fluffy and creamy.

Color frosting - Add some frosting into two small mixing bowls, about 3 tbsp in each. Color one with orange food gel, and mix. Color the other one with green food gel.

Add to piping bags - Add both colored frostings into separate piping bags fitted with small round tips.

Once cooled, add the cream cheese frosting on top of the cake and spread evenly. Sprinkle with crushed walnuts. Then pipe little triangles of orange frosting for the carrots. Green frosting for the stalks.