Preheat oven to 350 degrees F. In a bowl, beat together eggs, pumpkin, granulated sugar and apple sauce. Mix together the remaining ingredients, except brown sugar, in another bowl. Mix dry ingredients into wet until just combined. Spoon into a greased or paper cup-lined muffin pan. Sprinkle brown sugar on top of the muffins before baking. Bake 25 minutes, or until a toothpick inserted in a muffin pulls out clean. Allow to cool for 10 minutes before removing from muffin pan.