Preheat oven to 350 and generously grease the 4 mini bundt pans and set them aside.

In a medium saucepan, melt the butter and let it simmer until the milk solids start to brown at the bottom. It will start to foam and it will be a medium honey color. Transfer the browned butter to a large mixing bowl.

In the large mixing bowl, using a rubber spatula or wooden spoon mix together the browned butter, cake mix, brown sugar, water, pumpkin puree, eggs, pumpkin pie spice, and cinnamon until all combined.

Pour the batter evenly among the mini bundt pans, about ⅓ cup of the batter in each pan. You will have batter leftover, but you will use it in the next batch that goes in the oven.

Bake the mini bundt cakes for _ minutes or until _. Let cool before inverting and removing the cake. Repeat process until the batter is gone and all cakes are made.

While waiting on all the cakes to cool, make the frosting.