1. Preheat the oven to 350°F (175°C) and grease a loaf pan.

2. In a large bowl, mash the bananas until smooth.

3. Add the brown sugar, caster sugar, and melted butter to the mashed bananas. Mix well.

4. In a separate bowl, combine the all-purpose flour, baking soda, baking powder, cinnamon, and cocoa powder. Stir until well combined.

5. Gradually add the dry ingredients to the banana mixture, stirring until just combined. Be careful not to overmix.

6. Pour the batter into the greased loaf pan and smooth the top with a spatula.

7. Bake for 50-60 minutes, or until a toothpick inserted into the center comes out clean.

8. While the banana bread is baking, prepare the chocolate drizzle. In a small saucepan, heat the condensed milk and golden syrup over low heat until well combined and heated through.

9. Remove the saucepan from heat and stir in the maple syrup. Allow the mixture to cool slightly.

10. Once the banana bread has cooled, drizzle the chocolate mixture over the top. Allow it to set before serving.