Preheat oven to 180 C, 10 mins before baking. Grease and line a 9x5 loaf pan and set aside.In a large bowl, whisk together eggs, buttermilk and oil until well beaten together.Add in mashed bananas, both sugars and vanilla and mix well.Sift in flour, baking soda and salt and mix in nicely, do not over mix.Add chocolate chips and fold in gently.Pour into greased loaf pan and bake in the preheated oven for about an hour (refer notes). Check at an hour by doing the toothpick test. Bake longer as needed until cooked through.