Step 1

Preheat oven to 180C/160C fan forced. Grease and line base and sides of a 20cm base measurement square cake pan.

Step 2

Beat butter and sugar together until pale and creamy. Add banana, egg and milk. Beat together until well combined. Add flour, cocoa, cinnamon and choc chips stir until well combined. Spoon into prepared pan and level top.

Step 3

Bake for 45 minutes or until a skewer inserted at centre comes out clean and top is golden brown. If cake is browning too quickly in oven, cover loosely with foil. Stand for 5 minutes in pan, then transfer cake to a wire rack to cool.

Step 4

Meanwhile, make caramel frosting by beating the butter, sugar and cinnamon together until light brown and very fluffy. Beat in milk until well combined.

Step 5

Spread top of cooled cake with caramel frosting. Slice and serve.