Preheat the oven to 350ºF. Line two 9x5" loaf pans with parchment paper or grease well with butter.

In a large bowl, whisk together flour, sugar, baking powder, baking soda and salt.

In a separate bowl, stir together mashed banana, melted butter, milk and eggs. Add to dry ingredients and fold together until combined with some floury streaks remaining. Add chocolate and peanuts and gently fold in.

Divide batter between baking pans and bake for about 55 minutes, until top springs back when pressed and a toothpick inserted in the center comes out clean. Cool for a few minutes in pans, then invert into a dishtowel and flip onto a wire rack to cool completely before slicing. If you're able to.