Add flour, sugar, baking powder, baking soda, cinnamon, salt, buttermilk. oil, eggs, and vanilla
In a large mixing bowl. With an electric mixer, beat the ingredients for 3 minutes.
Pour the batter into the prepared loaf pan. Use an offset spatula to smooth the top of the batter. Set aside.
Add sugar, cinnamon, and melted butter in a small bowl. Sprinkle topping on the top of the loaf of bread.
Use a knife cut in a light swirling motion for a marbled effect.
Bake at 350 degrees for 50 minutes. Test the center of the loaf of bread by inserting a toothpick. If it comes out clean, remove it from the oven to cool.
Set it aside for a few minutes to cool before slicing.
