Ingredients
Method
1.Preheat oven to 180°C (160°C fan forced). Line 16 holes of two 12-hole (⅓-cup/80ml) muffin pans with paper cases.
2.Beat butter and sugar in small bowl with electric mixer until light and fluffy. Beat in eggs, one at a time.
3.Transfer mixture to large bowl, stir in sifted dry ingredients, banana, sour cream and milk, in two batches. Drop ¼ cups of mixture into paper cases.
4.Bake about 30 minutes. Stand cakes in pans 5 minutes before turning, top-side up, onto wire racks to cool.
5.Divide ready-made white icing in half. Tint one portion blue, leave remaining portion white. Roll each colour, one at a time, between sheets of baking (parchment) paper until 5mm thick.
6.Using cutter, cut 2.5cm stars, quite close together, from both pieces of icing. Place white stars in the holes left in the blue icing. (If you like, you can also place the blue stars in the holes left in the white icing  we used the white stars only). Re-roll the blue icing with stars between sheets of baking paper, to ensure stars are in place.
7.Brush cake tops with a little jam. Using cutter, cut 8cm rounds from blue icing, position rounds on cakes.
You need two large (460g) overripe bananas to get the required amount of mashed banana.
Note