Preheat oven to 350°F degrees. Grease five small loaf pans.*
Make the Cinnamon-Sugar by combining the sugar and cinnamon in a medium bowl; set aside.
In a large bowl, whisk the flour, baking powder, baking soda, cinnamon and salt together until combined; set aside.
In another bowl, whisk both sugars and the eggs together until thickened and combined, about 45 seconds. Stir in the oil, sour cream and vanilla.
Using a rubber spatula, gently fold the wet ingredients into the dry ingredients until almost combined. Fold the cinnamon chips in. Batter should still be lumpy with a few spots of flour.
Spoon two heaping tablespoons of batter into each loaf pan. Sprinkle 1 1/2 teaspoon of the cinnamon-sugar on top. Spoon another 2 tablespoons of batter on top of the cinnamon-sugar, followed by another 1 1/2 teaspoon of the cinnamon-sugar. Evenly spoon the remaining batter on top, filling the pans about 2/3 full.
Sprinkle remaining cinnamon-sugar on top.
Bake for 28-33 minutes, or until tops are golden brown and a toothpick inserted in the center comes out clean.** Allow loaves to cool in the pan for 30 minutes before transferring to a wire rack to cool completely.