Preheat the oven to 350 degrees Fahrenheit. Grease a light-colored loaf pan with non-stick cooking spray and set it aside.

In a large bowl, combine canola oil, softened butter, and granulated sugar until well mixed. Add eggs and vanilla extract, stirring until smooth.

Gradually add in the dry ingredients (flour, baking powder, and salt) and buttermilk, mixing until a uniform batter forms. Ensure there are no lumps by scraping the sides of the bowl.

Transfer 1/2 cup of the prepared batter into a separate smaller bowl. To this smaller portion, add cinnamon and molasses, stirring until combined.

Pour half of the plain batter into the bottom of the loaf pan. Spoon half of the cinnamon batter in small dollops over the plain batter. Pour the remaining plain batter over the cinnamon batter. Drop the remaining cinnamon batter on top. Using a butter knife, swirl the two batters together.

Bake for 45-50 minutes or until a toothpick inserted into the center comes out with a few moist crumbs.

While the loaf is baking, prepare the coating. Pour melted butter into a large shallow dish. In another shallow dish, combine granulated sugar, brown sugar, and ground cinnamon.

Allow the loaf to cool for 10 minutes before loosening the edges and removing it from the pan. The loaf should be warm enough to handle but not too hot.

Dip each side of the loaf into the melted butter until fully coated. Spoon any remaining melted butter over the edges for added crispiness. Transfer the buttery loaf to the cinnamon-sugar mixture and press it into the sides and top until fully coated.

Slice the loaf into pieces and serve warm or at room temperature. Enjoy your delicious cinnamon swirl donut bread!