This pumpkin chiffon cake is a delicious dessert that is perfect for fall. The cake is made with a combination of cake flour, sugar, eggs, oil, and baking powder, and is flavored with pumpkin puree and pumpkin pie spice. Once cooled, the cake is topped with a simple glaze made with powdered sugar and milk. Serve with a sprinkle of cinnamon for a delicious dessert.