In a large frying pan over medium heat, melt the butter. Whisk until it starts to foam and it is hard to see the bottom of the pan. The milk deposits will separate and turn brown. Remove from heat.
½ cup Plus 1 tablespoon Unsalted butter
Pour butter in a glass measuring cup and let it cool for 30 minutes.
Preheat the oven to 425°F. Line a muffin pan with 12 muffin liners. Set aside.
In a mixing bowl, sift the flour. Add in the brown sugar, baking powder, baking soda, cinnamon, salt, nutmeg, and pumpkin pie spice.
2 cups All-purpose flour, ¾ cup Brown sugar, 2 tablespoon Baking powder, 1 teaspoon Baking soda, 2 teaspoon Ground cinnamon, ½ teaspoon Salt, ¼ teaspoon Ground nutmeg, 1 teaspoon Pumpkin pie spice
In a separate bowl, Mix the brown butter, buttermilk, egg, pumpkin puree, vanilla, and sour cream. Pour the wet ingredients into the dry. Mix until combined. Fold in the mini chocolate chips.
½ cup Buttermilk, 1 Large egg, 1 cup Pumpkin puree, 1 teaspoon Pure vanilla extract, ¼ cup Sour cream, 1 cup Mini chocolate chips
Scoop the muffin batter and fill the liners ¾ full.
Bake for 10 minutes. Then, turn the oven to 375°F. Bake for another 8-10 minutes. They are done baking when a toothpick inserted comes out clean.
Let the muffins sit for 10 minutes before transferring to a cooling rack. Let the muffins cool slightly before enjoying.