Preheat oven to 350 degrees and line a 12-cup muffin tin with paper liners.

In a medium bowl, whisk together the gluten free flour, xanthan gum, baking powder, baking soda, salt, cinnamon, and nutmeg. Set aside.

In a large bowl, whisk together the eggs, pumpkin puree, granulated sugar, avocado oil, and vanilla extract. Add the dry ingredients to the wet ingredients and mix until just combined.

Transfer the batter to the muffin cups, dividing it evenly among the 12. Bake for 18-22 minutes or until a cake tester comes out clean. Cool completely on a wire rack before frosting.

To make the frosting, add the cream cheese and butter to the bowl of a stand mixer fitted with the paddle attachment. Beat together until smooth, about 1 minute.

Add the powdered sugar and mix on the lowest speed until the sugar is incorporated. Add the vanilla, lemon juice, and ground cinnamon. Then mix an additional 30 seconds to 1 minute until the frosting is smooth and creamy.

Frost the cupcakes with your favorite piping tip.