For the cupcakes:

1. Adjust oven rack to middle position and preheat oven to 350 degrees F.
2. In a large bowl, combine all dry ingredients. Mix with wire whisk. Make a well in the center. Set aside.
3. In a small bowl, combine eggs, pumpkin, and melted butter. 
4. Pour wet ingredients into well of dry ingredients. Using a spatula, gently fold wet ingredients into flour mixture. Do not overmix.
5. Line standard muffin tins with cupcake liners for 15 cupcakes. Using a 4 tablespoon cookie scoop, fill each about 3/4 full.
6. Bake 18-20 minutes, or until toothpick inserted comes out clean. Cool 5 minutes in pan and then turn onto wire rack to cool completely.

To make frosting:

1. In the bowl of a stand mixer fitted with the paddle, cream the softened butter and pinch of salt until light and fluffy. Scrape the bowl. Add the sifted powdered sugar, one cup at a time, and beat until smooth. Add 3 tablespoons of cream, maple syrup, and vanilla and continue beating until fully incorporated. If it seems a bit thick, add the extra T of cream. If you prefer a sweeter frosting, add another 1/2 cup of powdered sugar. 
2. Pipe frosting onto cupcakes or spread with an offset spatula. Sprinkle cinnamon or decorate with holiday sprinkles.