Preheat oven to 350°F (175°C). Grease a 9x5-inch loaf pan with butter or non-stick spray.

In a medium bowl, sift together flour, baking powder, and salt. Set aside.

In a large mixing bowl, blend canola oil, softened butter, and granulated sugar with an electric mixer until light and fluffy (about 3-4 minutes).

Beat in eggs one at a time, ensuring each is fully incorporated before adding the next. Add vanilla extract and mix well.

Gradually add dry ingredients to the wet mixture in three parts, alternating with buttermilk. Begin and end with the dry ingredients, mixing until just combined.

Transfer ¾ cup of the batter to a separate bowl. Add brown sugar, ground cinnamon, and molasses; mix thoroughly.

Pour half of the plain batter into the prepared loaf pan. Drop half of the cinnamon swirl mixture in small dollops on top. Use a knife or toothpick to swirl.

Pour the remaining plain batter over the marbled layer. Spoon the remaining cinnamon mixture on top and swirl again.

Place the loaf pan in the oven. Bake for 45-50 minutes, or until a toothpick inserted into the center comes out mostly clean.

Let the bread cool in the pan for 10 minutes.

Meanwhile, melt remaining butter in a shallow dish. In another dish, combine granulated sugar, brown sugar, and ground cinnamon.

Remove the bread from the pan, place it on a wire rack, and gently dip each side into melted butter, then into the cinnamon-sugar mixture to coat. Allow to cool completely before slicing and serving.