Preheat the oven to 350°F (175°C). Grease and flour a 9x13 inch baking pan.

In a large mixing bowl, whisk together the granulated sugar, brown sugar, pumpkin puree, and vegetable oil until well combined.

Add the eggs one at a time, mixing well after each addition.

In another bowl, sift together the flour, baking powder, baking soda, salt, cinnamon, and nutmeg.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Pour the batter into the prepared baking pan and smooth the top.

Bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean.

Allow the cake to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.

In a mixing bowl, beat the softened cream cheese and butter together until smooth and creamy.

Gradually add the powdered sugar and vanilla extract, beating until well combined and fluffy.

Once the cake is completely cool, spread the cream cheese frosting evenly over the top.