Cut the bananas into pieces and crush them with a fork until you have a puree with chunks.
Mix the butter with the sugar until smooth, then add the eggs and vanilla and beat again to incorporate them.
Add mashed banana and buttermilk and mix again with mixer to incorporate.
Finish with the dry ingredients, flour, cocoa powder, baking powder and baking soda and the chocolate chips and mix with a spatula to incorporate them.
Bake in a preheated oven at 180°C for about 55 minutes until done. Then let it cool completely in its mold before gently unmolding it.
Enjoy with a touch of peanut butter or Nutella and a good coffee for breakfast.