Preheat the oven to 350F (180C). Butter a 9x5 inches (23x13cm) loaf pan and line it with parchment paper.
In a medium bowl whisk flour with salt, baking powder, baking soda and cinnamon. Set aside.
In another bowl mix butter with sugar and vegetable oil until creamy. Incorporate eggs one at a time. Add vanilla extract and mix to combine.
With the mixer on low, gradually incorporate flour mixture alternating with buttermilk, until all is incorporated.
Fold in the semisweet chocolate chips and set aside.
In a small bowl mix sugar with cinnamon.
Pour up to half of the batter into the prepared loaf pan. Sprinkle half of the cinnamon sugar.
Cover with the remaining batter. Sprinkle the remaining cinnamon sugar.
Bake for about 40-45 minutes or until a toothpick inserted into the center comes out clean. If it browns too fast, you can cover it with aluminum foil and continue baking.
Allow cooling into the pan onto a rack for about 5-10 minutes. Remove from the pan and cool completely.