Preheat your oven to 180°C (350°F). Line a baking sheet with parchment paper and lightly grease it with butter.
In a large bowl, whisk the eggs until they are frothy and light. Gradually add the sugar, flour, cinnamon, baking powder, and pumpkin puree.
Mix everything together with a spatula until well combined and smooth.
Pour the batter onto the prepared baking sheet, spreading it evenly to create a thin layer.
Bake for 10-13 minutes, or until the edges are golden and the cake is firm to the touch.