Preheat oven to 350 degrees. Lightly grease a 9 x 5 inch loaf pan. In a small bowl, mix together 1/3 cup sugar and 2 teaspoons cinnamon; set aside

In a large bowl combine flour, baking powder, salt and remaining 1 cup sugar. Combine egg, milk and oil; add to flour mixture. Stir until just moistened

Pour half of the batter into the pan. Sprinkle with half the reserved cinnamon/sugar mixture. repeat with remaining batter and cinnamon/sugar mixture. Draw a knife through bater to marble.

Bake for 45 to 50 minutes, or until a toothpick inserted into center of the loaf comes out clean. Cool in pan for 10 minutes before removing to a wire rack to cool completely. Wrap in foil and let sit overnight before slicing.