Many years ago when I was a waitress, one of my dear customers gave me this recipe. This is the best tasting Banana Bread I've ever had! The vinegar you use to make the sour milk can change the taste of the bread, so feel free to experiment! Balsamic vinegar brings depth to the flavor, and apple cider vinegar gives a lighter, fruitier flavor. I often make several loaves at a time and store them in the freezer in zip-top plastic bags.