Sweet Potato Muffins

Ingredients:
2 ½ cups of All Purpose Flour
2 tsp of Baking Powder
½ tsp of Salt
2 tsp of Pumpkin Pie Spice
2/3 cup of Whole Milk
½ cup of Sweet Potato Puree
1 tsp of Vanilla Extract
½ cup of Sugar
¼ cup of Brown Sugar
½ cup of Vegetable Oil
2 Eggs

For the Topping:
½ cup of Unsalted Butter, melted
½ cup of Sugar
1 tsp of Pumpkin Pie Spice