1. Make the Macaron Shells:

1. Prepare baking sheets: Line two baking sheets with parchment paper or silicone mats.
2. Sift the dry ingredients: In a bowl, sift almond flour, powdered sugar, cinnamon, and nutmeg together. Discard any large bits.
3. Whip egg whites: In a clean bowl, beat egg whites with an electric mixer until foamy. Slowly add granulated sugar and continue beating until stiff peaks form. Mix in vanilla extract and orange food coloring (if using).
4. Macaronage: Gently fold the dry ingredients into the whipped egg whites using a spatula. Continue folding until the batter flows like lava when dropped from the spatula.
5. Pipe the macarons: Transfer batter to a piping bag fitted with a round tip. Pipe 1-inch circles onto the prepared baking sheets. Tap the trays on the counter to remove air bubbles.
6. Rest the macarons: Let the shells sit at room temperature for 30-60 minutes, until they develop a skin and are no longer sticky to the touch.
7. Bake: Preheat oven to 300°F (150°C) and bake for 12-14 minutes, until the macarons are set and have “feet.” Let cool completely.

2. Make the Pumpkin Pie Filling:

1. In a bowl, beat butter until creamy.
2. Add powdered sugar, pumpkin puree, cinnamon, nutmeg, and vanilla extract. Mix until smooth.
3. If needed, add heavy cream to reach desired consistency.

3. Assemble the Macarons:

1. Pipe the pumpkin filling onto half of the macaron shells.
2. Place the remaining shells on top and gently press to create a sandwich.
3. Refrigerate for at least 24 hours for the best texture and flavor.