Grease or line with paper lines a muffin pan. Set aside.
In a large mixing bowl, whisk together flour, baking soda, baking powder, spices, salt and brown sugar.
In another mixing bowl, whisk together pumpkin puree, oil, milk, vanilla and eggs.
Add the wet ingredients to the dry ingredients and stir in until just incorporated, no flour streaks remain. Do not overmix! Batter should be lumpy.
Place 1 and ½ tablespoon (I used a cookie scooof batter in each muffin cup. Place a teaspoon of Nutella in the center. Top with another 1 and ½ tablespoon scoop of pumpkin batter.
Bake the muffins for 19 to 23 minutes.
Let cool in pan for 5 minutes. Transfer onto a cooling rack.
Once cooled, drizzle the muffins with leftover Nutella.