Preheat the oven to 350°F. Line a 12-cup muffin pan with cupcake liners.
In a stand mixer with the paddle attachment, combine the flour, brown sugar, baking powder, baking soda, salt, cinnamon, and pumpkin pie spice together. In a separate bowl, whisk the oil, eggs, pumpkin, and vanilla extract together until combined. Pour about half of the wet ingredients into the dry ingredients and mix. Start on a low speed to combine and then bump it up to high speed and mix until light and fluffy, 3-5 minutes. Scrape the bowl, add the remaining wet ingredients, and mix just until combined, scraping as necessary.
Spoon the batter into the liners to about 2/3 full until all twelve are equally filled. Bake in preheated oven for 20-22 minutes, or until a toothpick inserted in the center comes out clean. Remove cupcakes from muffin pan and allow the cupcakes to cool on a wire rack completely before frosting.
To make the frosting:
Blend butter and cream cheese together on high speed in a stand mixer with the paddle attachment until light and fluffy, about 5 minutes. Scrape sides, add vanilla and orange zest, and continue mixing for about another minute or so, scraping the sides as needed.
Add sugar incrementally, blending slowly to combine and then on high speed to really mix. Scrape well and mix once more to fully combine.
To frost the cupcakes:
Ensure cupcakes are completely cool, then frost however you’d like. I used a disposable piping bag with a large round tip.
Notes
Make Ahead Instructions: Cupcakes can be made ahead 1 day in advance, covered, and stored at room temperature. Frosting can also be made 1 day in advance, covered, and stored in the refrigerator until ready to use. If refrigerated, frosting will need to come to room temperature before adding to cupcakes.
Storage: Leftover cupcakes keep well covered tightly in the refrigerator for 3 days. Frosted or unfrosted cupcakes can be frozen up to 2-3 months. Thaw overnight in the refrigerator.
Substitutions: Instead of prepared pumpkin pie spice, you can use 1 teaspoon of cinnamon plus 1/2 teaspoon each: ground allspice and ground ginger AND 1/4 teaspoon each: ground nutmeg and ground cloves. Oil: You can replace with unsweetened applesauce. Pumpkin: I used canned pumpkin but you may roast fresh. Just be sure to prepare at least a day ahead of time so that it has time to release excess liquid which you can squeeze out.
Recipe makes 12 cupcakes. Nutritional info based on one cupcake.