1. Preheat oven to 350F. Line standard muffin tins with paper liners; set aside.
2. In a medium bowl, sift together flours, baking powder, salt, and 1 tablespoon cinnamon.
3. In the bowl of an electric mixer on medium speed, cream butter and sugar together until light and fluffy. Add eggs, one at a time, beating well after each addition, scraping down the sides of the bowl as needed. Add vanilla extract. Reduce speed to low. Add flour mixture in 3 batches, alternating with 2 additions of milk, and beating until combined after each.
4. Divide the batter evenly among lined cups, filling each about three-quarters full (about 2 tablespoons batter). Bake, rotating halfway through, until a cake tester inserted in the center of a cake comes out clean, about 20 minutes. Allow to cool in tins for 10 minutes before transferring to a wire rack to cool completely.