Preheat the oven to 375 degrees Fahrenheit. Line a muffin pan with cupcake wrappers.
In a large bowl, combine the the butter and sugar, and mix on low speed until light and fluffy. Scrape the sides down as needed.
Add the eggs, and mix until just combined.
In a separate bowl, whisk together the flour, baking powder, salt, and cinnamon. Set aside.
In another bowl, stir together the milk, maple syrup, and vanilla extract.
Add the flour and milk mixture alternatively to the butter and egg mixture. Add 1/3 of the flour mixture, then stir till combined. Then 1/2 of the milk, and stir until just combined. Repeat again with 1/3 more flour, the remaining milk, then the rest of the flour. Stir until they're all combined together.
Fill the cupcake liners 3/4 of the way full with the batter.
Bake the cupcakes for 15 to 17 minutes, or until a toothpick comes out clean.