Cream butter, sugar, salt and cinnamon until fluffy. Add eggs and mix well. Add vanilla and sour cream and mix well. Mix flour and baking powder in a separate bowl. Add to wet ingredients and mix until all combined. Add cinnamon chips and stir into batter. Set aside. Spoon batter into 4 mini loaf pans until about 2/3 full. Mix 3 T. sugar and 3 t. cinnamon in a bowl and sprinkle over the batter in each loaf pan. Bake at 350 for 35-38 minutes. Let cool before removing from pan.