Preheat oven to 350°F. Grease your pan and line it with parchment paper.
In a small bowl, mix together your flour, cinnamon, and baking powder.
In your mixing bowl, beat together the eggs, sugar, and pumpkin until combined. Don't over-beat the eggs.
Add the flour mixture and beat to combine, but avoid over-mixing!
Pour your batter evenly over the parchment paper and spread it out.
Bake for 15 minutes.
Remove from the oven and let cool for five minutes.
Roll up your cake carefully, rolling with the parchment paper still attached. Move the roll to your cooling rack and allow to fully cool.
While cooling, combine your filling ingredients and beat into an icing.
Carefully unroll your cake. Spread the filling across the cake evenly, careful not to tear up the cake as you spread it.
Roll your cake back up, peeling back the parchment paper as you roll this time; the icing will help stick it together.
Cover the cake and let chill for 30 minutes. Dust lightly with powdered sugar and slice to serve!