Here's a formula that I got from my mother-in-law, modified slightly by yours truly:
Banana Bread
Fair Emelye's Bakery
Flour, All Purpose 13.500oz 380g 3 cups
Baking Powder 0.170oz 5g 1 tsp
Salt 0.070oz 2g ½ tsp
Vanilla extract 0.170oz 5g 1 tsp
Eggs, large 3.530oz 2 eggs
Sugar, granulated* 10.140oz 290g 1½ cups
Shortening 3.375oz 96g ½ cup
Baking Soda 0.170oz 5g 1 tsp
Buttermilk 4.000oz 113g ½ cup
Bananas 14.250oz 400g about 3 large very ripe
Sweet Spice Blend 0.200oz 6g 1½ tsp see below
Walnuts, Chopped 6.500oz 185g about a cup, optional
*The volume measurement is for American granulated sugar. Use the weight if using castor sugar.
Preheat oven to 325ºF (160ºC)
Dissolve baking soda in the sour milk. Cream the shortening and sugar, then add the buttermilk, eggs, sweet spice blend and vanilla. Mash the bananas and add them to the previous ingredients. Mix thoroughly. Sift the flour, salt and baking powder and stir them into the wet ingredients one third of the quantity at a time. Divide the batter equally into two greased bread pans.
Place in the middle rack of the oven and bake at 325ºF (160ºC) for 10 minutes, then increase the oven temperature to 375º (190ºC) and bake an additional 45 minutes or until a toothpick inserted into the thickest part of the loaf comes out clean. Let the loaves cool in the pans while they are lain on their sides on a cooling rack for 20 minutes before removing the loaves from the pans.
Sweet spice blend
(I got this from Elizabeth David's "English Bread and Yeast Cookery" where she uses this blend for hot cross buns. It works very well in banana bread. I use allspice berries instead of the peppercorns and add cardomom as well, about ¼ part)
• 2 parts ground nutmeg
• Two parts ground white or black peppercorns or allspice berries
• One part ground cinnamon bark
• One part whole cloves, ground
• 1 part dried and ground ginger root
To this mixture a fraction of ground cumin seed or cardamom may be added
