Preheat the oven to 350 degrees F and grease two and line with a round of parchment paper cut to fit the inside of each pan. (Use the pan to trace the pan onto the paper, then cut out just inside the line.) Coat the top of the paper with nonstick spray, too.
Whisk together the sweet potato, oil, maple syrup, egg, and vanilla in a large bowl.
Stir in the flour, baking powder, baking soda, cinnamon and salt to just combine.
Divide the batter among the prepared pans, using about a heaping cup in each. Smooth to spread the batter evenly.
Bake for 18-20 minutes or until a cake tester inserted into the center comes out clean.
Transfer to a wire rack to cool for 5 minutes, then gently invert onto a wire rack to remove from pans and cool completely.
To make the frosting:
Add the cream cheese to a medium bowl with maple syrup and vanilla extract. Mix together with a whisk until fluffy. (If this is hard to do due to the temperature of your cream cheese, you can use an electric handheld mixer.)
To assemble the cake:
Place one cake on a cake stand or plate.
Spread about half of the frosting on top of one cake, add the second, then top with the remaining frosting, spreading smooth.
The cake can be made 24 hours before you plan to frost it. Let cool completely on a wire rack, then store in an airtight container at room temperature. (It's also fine to frost it the day before if you can carefully wrap it in plastic wrap and store in the fridge to keep it fresh.)
Store leftovers in the fridge once frosted for up to 3-5 days in an airtight container or wrapped with plastic.