Pumpkin Doughnut Muffins

Ingredients

• 1 1/4 sticks butter, room temperature, plus more for pan
• 3 cups all-purpose flour (spooned and leveled), plus more for pan
• 2 1/2 teaspoons baking powder
• 1/4 teaspoon baking soda
• 1 teaspoon coarse salt
• 1/2 teaspoon ground nutmeg
• 1/4 teaspoon ground allspice
• 1/3 cup buttermilk
• 1 1/4 cups pure pumpkin puree (from a 15-ounce can)
• 3/4 cup light brown sugar
• 2 large eggs
• 3/4 cup granulated sugar
• 2 1/2 teaspoons ground cinnamon
• 1/4 cup (1/2 stick) unsalted butter, melted