Pumpkin Madeleines

In a large mixing bowl, add the eggs and sugar. Use a stand mixer or hand mixer fitted with a whisk attachment to beat the egg mixture until it becomes very pale in colour and leaves trails when mixed, about 8 minutes. Mix in the pumpkin puree and vanilla extract until combined.
Sift in the flour, baking powder, and pumpkin pie spice. Use a spatula to gently fold together until just combined.
Add in the melted butter and fold until just combined and no streaks of butter remain.
Press a piece of plastic wrap directly onto the surface of the batter and chill in the fridge for at least 1 hour or overnight. It should become very spongey and airy.
Preheat oven to 400°F. Melt about 1 tablespoon of butter and use a pastry brush to brush a thin layer of melted butter on the madeleine pan.
Use a tablespoon or a small cookie scooper to scoop out about 1.5-2 tablespoons of batter into each madeleine mold. Leave the batter as is - it will melt and expand into the madeleine shape as it bakes.
Bake at 400°F for 5 minutes then turn down the temperature to 350°F for another 5-6 minutes until the tops are puffed and edges are golden brown.
Cool madeleines in the pan for about 10 minutes before transferring them to a wire rack to cool completely. Dust with powdered sugar before enjoying!