Step 1

Preheat oven to 350F

Step 2

Add the softened butter and banana to the bowl of a stand mixer, fitted with a paddle attachment, and mix until blended and smooth. (Or, if you don't have a stand mixer, mash the banana by hand with a fork, and add in the softened butter along with the rest of the ingredients)

Step 3

Add the egg and milk, vanilla, flour, sugar, baking soda, and salt, and mix until no lumps remain.

Step 4

Fold in the chocolate chips and walnuts until evenly distributed.

Step 5

Pour the batter into a prepared loaf pan, and bake for about 40-45 minutes, until risen and golden brown on top, and a toothpick inserted in the middle comes out without batter clinging to it. (Moist crumbs are fine.)