Preheat oven to 350 degrees.
In a standing mixer with the paddle attachment or by hand with a whisk, combine the oil and sugar.
In a small bowl combine the buttermilk, apple butter, orange zest, and vanilla.
Beat eggs into sugar and oil.
Combine the flour, salt, baking soda, and cinnamon.
Alternate adding the dry and wet ingredients into the batter just until combined.
Mash the bananas and fold into the batter.
Fold in the toasted walnuts and chocolate chips.
Coat the loaf pan with coconut oil and place a piece of parchment paper at the bottom of the loaf pan. Coat the top the parchment in oil as well.
Fill the loaf pan with the batter three quarters full.
Bake in the center rack for 55 minutes to one hour or until a toothpick or skewer inserted in the center comes out clean.
For the glaze:
While the bread is cooling melt the butter and brown sugar over medium heat.
Stir in the milk, vanilla, and baking powder and let bubble while continuously stirring for one minute.
Place the banana bread on a sheet pan to catch the excess glaze.
Immediately pour over the banana bread.
Slice and serve.