Preheat the oven to 180°C. Grease 8-10 hollows of a large muffin tin or 8-10 ramekins with non-stick spray or butter.
1. Cakes: In a large mixing bowl, beat the butter cubes and sugar with an electric beater until light and creamy.
2. Add the eggs one by one, beating well after each addition. Add the lemon and orange zest, cake flour, mealie meal or polenta, baking powder and salt. Beat until the ingredients are just combined.