Start by preheating your oven to 375°F (190°C). Grease a 10x15-inch jelly roll pan and line it with parchment paper.
In a large mixing bowl, beat the eggs and sugar until light and fluffy. Add the pumpkin puree, coconut oil, maple syrup, vanilla, and sourdough starter, mixing until smooth and well combined.
In a separate bowl, sift together the flour, baking powder, baking soda, salt, and pumpkin pie spice. Gradually fold the dry ingredients into the pumpkin mixture until just combined, taking care not to overmix.
Pour the batter into the prepared pan and spread it evenly. Bake in the preheated oven for 12-15 minutes or until the cake springs back when lightly touched.
Once the cake is done, immediately roll the cake (starting from the narrow end) along with the parchment paper. Careful! It's hot! This helps the cake cool in a rolled shape, making it easier to fill later. Let it cool completely.
In a mixing bowl, beat the cream cheese, butter, and vanilla until smooth. Gradually add the powdered sugar and salt, mixing until light and creamy.
Once the cake is fully cooled, carefully unroll it. Spread the cream cheese filling evenly over the cake, leaving a small border around the edges. Gently re-roll the cake without the parchment, being careful not to squeeze out the filling. Wrap it tightly in plastic wrap and refrigerate for at least an hour to set.
When ready to serve, dust the top with powdered sugar for a beautiful finish. Slice into rounds to reveal the creamy swirl inside.