1. Preheat your oven to 175°C (350°F). If using a non-stick loaf tin, no need to line it. Otherwise, grease and line your pan with parchment paper.
2. Mash the bananas with a fork until smooth and set aside. 
3. In a large bowl, whisk together the peanut butter and oil until smooth. Stir in the milk, vanilla extract, and sour cream until combined.
4. Add in the eggs, one at a time, mixing well after each addition. Then, add the light brown sugar and mix until fully incorporated.
5. Add the mashed bananas and mix them in well.
6. Place a sift on top of the mixing bowl, sift in together the flour, baking powder, and baking soda. Then add the salt.
7. Gradually fold the dry ingredients into the wet mixture using a spatula. Mix until just combined, ensuring no dry flour remains.
8. Pour the batter into the (prepared) loaf tin. Sprinkle crushed salted peanuts on top, gently pressing them into the batter with the handle of a spatula or the back of a spoon to prevent them from popping up during baking.
9. Bake in the preheated oven for 53-57 minutes, or until a toothpick inserted into the center comes out clean.  For your reference, mine took 55 minutes. 
10. Let the cake cool in the pan for about 15 minutes. Once cool enough to handle, remove from the pan and allow it to cool completely on a wire rack for at least an hour before slicing. This allows the loaf cake to settle and prevents crumbling or a sticky interior (it’s torture but worth the wait!).

Enjoy your peanut butter banana loaf cake with a cup of coffee or tea! This will keep well and for subsequent days, it’s delicious toasted and served with butter.