Preheat oven to 300° F. Grease two 9"x5" loaf pans and set aside.
In a medium bowl, mash bananas and eggs until they reach a smooth consistency with very few lumps.
In a stand mixer or large mixing bowl with a hand mixer, cream sugar and shortening. Add in vanilla extract and banana/egg mixture. Mix well. Sift flour, baking soda, baking powder, and salt together and slowly blend into batter.
Chop walnuts into small pieces and blend into batter. Divide batter evenly into prepared pans.
Bake for approximately 1 hour and 10 minutes to 1 hour and 25 minutes. Be careful not to over bake. Check for doneness by inserting a toothpick into the thickest part of the loaf and if it comes out clean it is done.