Preheat oven to 180°C. Grease and line the base of two 22cm round cake pans with baking paper.
Place butter and sugar in the bowl of an electric mixer and beat until light and fluffy. Add the eggs, one at a time, beating after each addition until just combined. Fold in the flour with a large metal spoon and divide the mixture evenly between 2 bowls. Add the pink food colouring to one bowl, and the cinnamon and cocoa to the other. Stir each to combine. Place the pink mixture in one pan and the chocolate mixture in the other, spreading each mixture evenly.
Bake on same shelf in the oven for 25 minutes or until a skewer inserted into the centre comes out clean. Set aside to cool slightly, then turn out onto a wire rack to cool.
Meanwhile, to make the icing, place the cream cheese, butter, icing sugar and vanilla in a medium bowl and use an electric hand beater to beat until smooth.
Halve the cakes horizontally by using a sharp knife to slice through centre of each cake. Spread 3 tablespoons of icing on one cake half and place a different coloured half on top. Spread with another 3 tablespoons of icing, then repeat the process. Use the remaining icing to completely cover the cake. Use a fork to make zigzag lines over the surface of the icing. Decorate perimeter of cake with eggs.
