1. Pre-heat oven to 350 F (180 C). Cream together the sugar and softened butter using electric beaters. Add the egg yolks and banana pulp and continue to beat until smooth. In a separate bowl, combine the flour, baking powder, salt, poppy seeds and cinnamon. Add this dry mixture to the banana pulp/egg mixture, then add the milk and combine all ingredients using electric beaters.
2. Line a cupcake pan with patty pan (cupcake) liners. Fill each liner ¾ full with the cupcake mixture. Bake for 15 minutes or until the cakes are golden brown on top. Let cool while preparing the icing.

For the icing

1. Combine the softened butter, icing sugar, milk and vanilla in a bowl; mix using electric beaters until smooth. Place mixture in a piping bag and pipe onto each cupcake. Optional: sprinkle a few poppy or chia seeds on top of each cupcake.