In a medium bowl, whisk together 3 cups flour, baking powder, salt and cinnamon. Set aside.
In a large mixing bowl, cream together butter and 2 cups sugar, until fluffy, about two minutes. Add eggs one at a time mixing well after each addition.
Add vanilla and sour cream and mix to combine. Add flour mixture and mix just until combine. Do not overmix. Coat the cinnamon chips with 2 tablespoons flour and stir into batter.