- 145g unsalted butter
- 250g granulated sugar
- 80g unsweetened cocoa powder
- 1/4tsp salt
- 1tsp vanilla extract
- 2 large eggs
- 65g plain flour
- 2 bananas
- 75g chopped walnuts or pecans, optional
Position an oven rack in the middle of the oven and heat to 160°C. Line the bottom and sides of an 8-inch square baking pan with parchment paper or aluminium foil, leaving an overhang on two opposite sides. This helps when removing the baked brownies from the pan, once cooled.
Add enough water to a medium saucepan so that it is 1 to 2 inches deep. Heat water until barely simmering. Combine butter, sugar, cocoa powder, and the salt in a medium heat-safe bowl. Rest the bowl over simmering water (if the bottom of the bowl touches the water, remove a little water).
Stir mixture occasionally until the butter has melted and the mixture is quite warm. Don’t worry if it looks gritty; it will become smooth once you add the eggs and flour. Remove the bowl from heat and set aside for 3 to 5 minutes until it is only warm, not hot. Stir in the vanilla with a wooden spoon or spatula. Add eggs, one at a time, stirring vigorously after each one. Then add the chopped bananas into the warm mixture – this will make it easier to mash into the batter.
When the batter looks thick, shiny and well blended, add the flour and stir until the ingredients are fully mixed in. Then beat with the wooden spoon or spatula until the batter is thick. You want to see the brownie batter pulling away from the sides of the bowl. You can do this by hand or using a mixer. Stir in the nuts, if using, and spread evenly in a lined pan.
Bake the mixture for 20 to 25 minutes or until a toothpick can be inserted into the centre and come out almost clean (you want it to be a little moist with batter). Cool completely then remove from pan.