Step 1: Brown the butter. In a light-colored saucepan, melt the unsalted butter over medium heat. Stir constantly until it turns a golden-brown color and nutty brown bits form at the bottom. Immediately pour into a heat-safe bowl and let cool slightly.
Step 2: In a medium bowl, whisk together the flour, baking soda, baking powder, cinnamon, nutmeg, ginger, cloves, and salt. Set aside.
Step 3: In a large bowl, combine the slightly cooled brown butter with granulated sugar and brown sugar. Beat with an electric mixer until light and fluffy, about 2 minutes.
Step 4: Add the pumpkin puree, egg, vanilla extract, and maple extract (if using) to the butter mixture. Beat until well combined.
Step 5: Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined. Be careful not to overmix.
Step 6: Cover the dough and chill in the refrigerator for at least 30 minutes, or up to 2 hours. Chilling helps prevent the cookies from spreading too much.
Step 7: Preheat oven to 375°F (190°C). Line baking sheets with parchment paper or silicone mats. Use a medium cookie scoop (about 1.5 tablespoons) to drop dough onto the prepared baking sheets, leaving about 2 inches between cookies.
Step 8: Bake for 12-15 minutes, or until the edges are set and lightly golden, but the centers still look slightly soft. They will firm up as they cool.
Step 9: Let cookies cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.
Step 10: Once cookies are completely cool, melt the white chocolate or white candy melts. You can do this in a microwave in 30-second intervals, stirring well after each, or over a double boiler. Transfer melted white chocolate to a piping bag with a small round tip or a Ziploc bag with a tiny corner snipped off.
Step 11: Pipe ghost shapes onto the cooled cookies. Don't worry about perfection; slightly irregular shapes add to the charm.
Step 12: While the white chocolate is still wet, melt the black candy melts (if using) or use black icing gel to create two small dots for the ghost eyes. Alternatively, you can use a toothpick dipped in black food coloring.
Step 13: Allow the white chocolate ghosts to set completely before storing. You can place them in the refrigerator for 5-10 minutes to speed up the setting process. Enjoy your spooky treats!