Heat oven to 160° C or Gas Mark 3.
Combine the flour, cinnamon, baking powder, and salt - set aside.
In a large bowl,or the bowl of a standing mixer, cream the butter and sugar together until light and fluffy.
Add the eggs, one at a time, until just combined
Remove from stand mixer and stir in the vanilla and oil.
Sprinkle 1/3 of the flour mixture over the butter mixture and gently stir in until barely combined. Add half of the milk, mixing until just combined. Repeat these steps with the remaining flour mixture and milk, ending with the flour. Do not over mix.
Fill each cup cake tin with 2 tablespoons of batter, or until the cupcake tin is filled half way. Bake the cupcakes for 14 to 16 minutes, or until a toothpick inserted in the centre comes out with one or two crumbs clinging to it. Allow the cupcakes to cool completely before frosting.