In a bowl of a mixer, cream together the sugar and shortening (or butter) until light and fluffy, about 2 minutes. Reduce speed and add eggs one at a time, mixing until combined. Add mashed bananas and mix well.
In a small bowl, whisk together the flour, baking soda, baking powder and salt. Add to banana mixture and mix until just combined. Remove bowl from mixer and stir in nuts, if using.
Scrape batter into a loaf pan and place in the oven. Set timer for 10 minutes. After 10 minutes, reduce heat to 350 degrees and bake for 45 to 50 minutes, or until the top no longer looks moist and the sides are beginning to pull away from the pan.
Let sit for 5 minutes on a wire rack, then run a knife along the edges and invert loaf onto the rack to cool completely.
Nutrition information per each of 12 slices:
Calories278Fat13 gSodium148 mg