1. Heat oven to 350°F Line 12 mini cupcake pan indents and 12 regular indents with foil or paper liners. Line 6 jumbo cupcake indents with foil or paper liners.
2. For cupcakes: In a medium-size bowl, whisk flour, pumpkin pie spice, baking soda, baking powder and salt together until well blended; set aside.
3. Beat sugar, vegetable oil, buttermilk, pumpkin puree and eggs in a large bowl on low speed for 2 minutes or until combined. Add flour mixture and beat for 2 more minutes or until just combined.
4. Divide among liners, filling each about 2/3 full.
5. Bake at 350°F for about 12 minutes for the minis, 18 minutes for the regulars and 26 minutes for the jumbos, or until a toothpick inserted in the center comes out clean. Transfer to a wire rack and cool completely.
6. For frosting: Beat cream cheese and butter in a large bowl on high for 3 minutes or until light and fluffy. Gradually add the confectioner's sugar, vanilla and milk and beat until smooth and a good spreading consistency, 2 minutes. Add an additional tablespoon of milk if mixture is too thick.
7. Divide the frosting into two bowls and tint to different shades of orange with food coloring. Mound the frosting on top of cupcakes and make rounded. Roll the entire cupcake in the sugar to coat or roll just edges in sugar, alternating between fine and corase sugars as desired. To make indentations, press a wooden skewer on top of the sugared cupcake. Add pretzel sticks or rods as stems.