Preheat oven to 350 degrees. Grease & flour a 9x5x3-inch loaf pan.
Cream sugar and shortening in a medium bowl. This can be done by hand with a potato masher or fork or with an electric mixer.
Add eggs and mix well.
Mash bananas and add to creamed mixture. Stir.
In another bowl, combine flour, baking soda and salt. Add to wet ingredients. Stirring until incorporated.
Take out 1 cup of batter and move to another bowl.
Add vanilla extract to the original batter and stir.
Using a microwave safe dish, melt unsweetened chocolate in microwave in 30-second increments, stirring in-between until chocolate is melted. It usually takes 60-90 seconds.
Stir melted chocolate into 1 cup of batter until well mixed.
Pour vanilla banana bread batter into prepared pan and top with chocolate batter. Swirl with knife.
Bake for 60-75 minutes or until toothpick in center comes out clean. Check after first 40 minutes to make sure top is not getting overly brown. If so, tent with aluminum foil until done.
Toothpick inserted in enter should come out with moist crumbs only when it is done.
Remove from oven and let cool in pan on wire rack for 10-15 minutes. Remove loaf from pan. Place on wire rack and let cool completely.
No shortening? You can substitute butter in the same quantity but the final result may not be quite as light or fluffy.
Make sure the bananas you are using are very ripe. You know those ones that are ugly and brown and no one wants to eat. These are perfect for baking as the starch has turned to sugar and makes them a sweet addition to any recipe.
When mixing the batter, make sure to do so by hand to eliminate any over mixing. The more you mix the batter the more gluten is formed. This can make a quick bread dense and rubbery as opposed to tender and soft.