Preheat oven to 350 degrees F, and line your muffin tin with muffin cups, or grease liberally with butter or coconut oil.
In a large mixing bowl, combine the cinnamon, flour, cornmeal, baking powder, baking soda and salt. In another bowl, combine the butter, sugar, eggs, canned pumpkin, and buttermilk and whisk until blended.
Slowly fold the dry ingredients in with the wet just until combine. Fill each muffin cup 3/4 full - you may get anywhere from 12-15 muffins.
Bake for 15-17 minutes or until a toothpick inserted in the center of a muffin comes out clean.
Serve with warm whipped butter, if desired.