Preheat oven to 350 degrees.
Prepare cupcake pan by placing liners in the pan.
In a large bowl combine sugar, cake flour, baking powder, baking soda, and salt. Mix until a mixer, on low until combined.
Add butter, mix on low for about 2 minutes. Batter will be crumbly.
Whisk the eggs, sour cream, cinnamon, and vanilla together until the texture is smooth.
Pour the liquid mixture in with the dry ingredients beating until combined on medium.
Reduce speed to low while gradually adding milk to the above mixture.
Spoon the batter into the lined cupcake tins until 2/3of the way full.
Bake on 350 degrees for 12-15 minutes or until an inserted toothpick comes out clean.
Take out of oven allowing the cupcakes to remain in the cupcake pan to cool for several minutes.
Transfer the cupcakes to a wire rack until totally cool.
While cupcakes are cooling, scoop some cereal into a small ziplock bag and use a rolling pin to crush the cereal.