For The Gluten-Free Pumpkin Cupcakes:

1. Preheat the oven to 350 degrees F. Line a muffin pan with parchment liners or grease well to avoid sticking.
2. In a medium bowl, combine the dry ingredients. Stir together flour, baking powder, baking soda, salt, cinnamon, ginger, nutmeg, cardamom, and cloves. Whisk until well combined and no large clumps of flour remain. 
3. In a large bowl or a stand mixer, combine the wet ingredients. Mix pumpkin puree, brown sugar, eggs, oil, milk, and vanilla. Whisk or mix until smooth. 
4. Add dry ingredients to the wet ingredients and stir until just combined. Try not to overmix. Just stop mixing when there aren’t any large clumps of dry ingredients remaining.
5. Scoop the cupcake batter into your prepared muffin cups, filling each cup only 2/3 full (if you end up filling them 3/4 full, you won’t have as many cupcakes and may need to bake them longer.)
6. (Note: You’ll likely have 14-16 cupcakes total, so you’ll need to bake the last few in a second batch, or you can use a second muffin pan, if you have one.)
7. Bake the cupcakes at 350 degrees F. for 17-20 minutes, or until a toothpick inserted in the center comes out clean with just a few moist crumbs and the tops of the cupcakes spring back when gently pressed with your finger. Let the cupcakes cool 2-3 minutes in the muffin tin before transferring them to a wire rack to finish cooling completely.
8. Bake any remaining cupcakes, as needed. 
9. Allow the cupcakes to cool completely before frosting them.

For The Cinnamon Cream Cheese Frosting:

1. In a large mixing bowl or a stand mixer, combine butter and cream cheese. Beat until smooth and well combined. 
2. Add 3.5 cups powdered sugar, as well as the vanilla, cinnamon, and salt. 
3. Beat the frosting on low for about 30 seconds while the powdered sugar is getting incorporated, then beat on medium speed about 2 minutes. The frosting will be lighter in texture and color as more air is incorporated.
4. If you plan to frost the cupcakes (rather than pipe the icing), you’ll want to check the frosting texture here. It’ll be soft, but shouldn’t be drippy or too loose. You may want to add an additional 1/2 cup of powdered sugar if your frosting seems too soft. Spread the frosting on cooled cupcakes and decorate with any desired garnishes, like caramel sauce, cinnamon sticks, pecans, sprinkles, or a pinch of cinnamon. 
5. If you plan to pipe the frosting onto the cupcakes, you’ll need to make sure the frosting is stiff enough to hold its shape. This means adding an additional 1-1.5 cups powdered sugar. Start 1/2 cup at a time, beating to incorporate the powdered sugar after each addition, until your frosting can easily hold its shape. (You can test this by dolloping a bit on the edge of a butter knife and seeing how the frosting behaves. If it drips off or spreads, it’s likely too soft. Keep adding powdered sugar until you reach the right consistency. For me, this is usually at the 4.5 cup mark, though if your kitchen is hot, or the butter has gotten warm, you may need a full 5 cups.) Pipe the frosting onto the cooled cupcakes as desired, and top with any desired garnishes, like caramel sauce, cinnamon sticks, pecans, sprinkles, or a pinch of cinnamon. 
6. Store leftover pumpkin spice cupcakes in an airtight container in the refrigerator up to 3 days, or freeze up to 1 month. (FYI: They’ll freeze better unfrosted!)