Pumpkin Doughnut Muffins

Preheat oven to 350º F. Grease 12-18 muffin cups (or line with paper) and set aside.
In a medium bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon, and ginger; set aside.
In a smaller bowl, stir together the buttermilk and pumpkin; set aside.
In a large bowl of a stand mixer (or with a hand mixer), beat the butter and brown sugar on medium speed until light and fluffy, about 3 minutes.
Add eggs, one at a time, and mix well.
Add half of the flour mixture to the butter/sugar mixture and mix on low speed. Then add half of the pumpkin mixture and mix on low speed.
Repeat with the rest of the flour mixture and pumpkin mixture.
Fill greased muffin tins roughly 3/4 full of batter and bake in preheated oven for about 20-23 minutes (until a toothpick inserted into the center of the muffin comes out clean).
Let the muffins cool on a wire rack for about 10 minutes.
While the muffins cool, melt 1/4 cup butter in a small bowl and mix together the cinnamon and sugar in another small bowl.
Roll or dip the muffins completely in butter and then roll or dip them in the cinnamon/sugar mixture until they are fully coated.
Let the muffins cool completely on a wire rack.