• Preheat the oven to 350° F. Grease and flour two 9-inch round spring-form pans or cake pans. Cut a round of parchment paper to fit into the bottom of the pan. Grease and flour the parchment paper.
• In a large bowl, whisk together the flour, cornstarch, baking powder and salt. Set aside.
• In the bowl of a large stand mixer, beat the softened butter with the 1 ½ cups of granulated sugar for about 5 minutes: the mixture should be fluffy and pale yellow in color. With the mixer running on low, slowly pour in the egg whites and vanilla, and mix them into the butter-sugar mixture.
• Add to the mixing bowl a third of the flour mixture and run the mixer until it is just combined. Add in half of the milk and mix this in too. Repeat these steps with another third of the flour mixture, then the rest of the milk and then finally the last of the flour mixture. The batter should be smooth.
• Divide the batter evenly between the two prepared cake pans. Bake the cakes for 30 minutes.
• While the cakes bake, prepare the lemon syrup: to a small saucepan add the ½ cup of granulated sugar and the lemon juice. Stir these together and heat the mixture over medium heat. Stir occasionally while you bring it to a boil. Once it's boiling, reduce the heat slightly and simmer for 5 minutes, stirring it occasionally. After 5 minutes, remove the pan from the heat. Allow it to sit and cool slightly while the cakes finish baking.
• After the cakes have baked for 30 minutes, check them by inserting a toothpick or wooden skewer into the center - it should come out clean. If necessary, bake the cakes a few minutes longer until the tester comes out clean.
• Remove the pans from the oven and place them on a cooling rack. Use a pastry or silicone brush to brush the tops of the hot cakes with the lemon syrup. Stop when the tops of the cakes seem moistened - you will not need all of the syrup. The remaining syrup can be poured into a jar and refrigerated for up to two weeks (or you can discard it.)
• Allow the cakes to cool completely. Remove the cakes from the pans and peel off the parchment rounds. Wrap the cakes in plastic wrap and refrigerate the layers for at least 1 hour or up to two days.

While the cake layers chill, prepare the coconut and frosting:

• Place the coconut in large gallon-size Ziploc bag. Add in a few drops of the green food coloring plus 1 teaspoon of water. Seal the bag and gently squeeze it to mix the green through the coconut. Repeat as necessary with more green food coloring and water until you get the shade of green you want, to look like grass on the cake. Keep the coconut sealed in the bag until you're ready to use it.
• To prepare the buttercream, beat together the ¾ cup of butter and the ¼ cup of vegetable shortening in the bowl of a stand mixer. Mix in the salt. Beat in 1 cup of the confectioner's sugar, followed by a little of the milk. Continue alternating the sugar and milk until all of the sugar has been mixed in. Add in the vanilla and beat the frosting until it is light and fluffy. (You may not need all of the milk.)
• Scoop out 1 cup of the frosting and place it in a small bowl. Add in a few drops of the yellow food coloring and mix it in with a fork. Continue adding food coloring until you get a nice shade of yellow that is bright and chick-like! (If the frosting gets too soft add in a little confectioner's sugar.)

Assemble the cake:

• Remove one cake layer from the fridge and unwrap it. Place it on a round cake platter. Spread about 1 cup of the buttercream over the layer and to the edge all the way around. Make the frosting even across the layer with a slight rise around the edge.
• Spoon the lemon marmalade over the frosted layer and spread it evenly to within two inches from the edge.
• Remove the second cake layer from the fridge, unwrap it and place it on first layer. Spread a thin layer of buttercream over the top as a crumb coat. Spread a thin layer of frosting as a crumb coat over the sides as well. If there are gaps between the layers, use buttercream to fill them in. Spread the remaining butter cream over the sides and over the top layer, Touch up and fill in gaps along the sides or in places where cake is showing.
• Spread some green coconut over the top of the cake and gently press it into frosting. Sprinkle more coconut over the top so it looks fluffy. If the cake top is not quite flat, build coconut up at edges and make it flatter through center where the chicks will be.
• Place the reserved, yellow frosting in a piping bag with a #12 tip. Or, place the yellow frosting in a medium Ziploc bag, and snip off one corner to make about a ¼-" opening. To make a chick, pipe a mound of yellow frosting onto the coconut (for the chick body) and then on top of this a smaller mound (for the head.) If the yellow frosting is too soft and not holding its shape, refrigerate it for 10-15 minutes until it is more firm.
• Repeat these steps to make several chicks over the top of the cake (I did nine and had frosting leftover.)
• Push two chocolate sprinkles into each head to create two small, black eyes on each chick. Place the triangle sprinkle under the eyes with the corner sticking up and out slightly to make a beak on each head. Place a yellow oval sprinkle on the top of each head, on its side and sticking up to look a like a tiny chicken's comb.
• Slice the cake and serve. Keep leftover cake in a covered cake storer for up to three days. Serves 10 people.