Preheat the oven to 180ºC. Grease a madeleine tin or a 12-hole shallow muffin tin with butter and dust with flour. Tap out the excess flour.Combine the butter and maple syrup. Add the eggs and vanilla extract to the butter and whisk together.Sift the flour, baking powder, spices and salt into a mixing bowl.Add the wet ingredients into the flour and whisk until the flour is incorporated. Don't over work the batter.Lastly, add the pumpkin puree and stir thoroughly to combine. Set the batter aside to rest for 5 minutes.Spoon into the prepared moulds, tap to remove air bubbles and bake for 10-12 minutes until golden and puffy.Cool on a wire rack before dusting with powdered sugar. Serve as is or with a pot of warm caramel for dipping or drizzling.