In a mixing bowl, add cream cheese and sugar. Using an electric mixer, cream together the cream cheese and sugar until combined, scraping the sides of the bowl as needed. Add egg and vanilla extract and beat until combined. Set aside.

Line the base and sides of an 8x8 or 9x9 inch square pan with parchment and preheat the oven to 375℉/190℃.

In a medium bowl, whisk together flour, baking powder, salt, and pumpkin spice. Set aside these dry ingredients.

In a medium heat-proof bowl, place white chocolate and butter. Place the bowl over a saucepan of simmering water and stir occasionally until chocolate and butter have melted. Transfer mixture to a large bowl. Add brown sugar and mix to combine. Add egg, pumpkin, and vanilla and mix until smooth.

Using a medium mesh strainer, sift in the dry ingredients then fold just until combined. Spoon mixture into pan.

Place cream cheese topping in a piping bag or ziploc bag. Cut ¼ inch opening on one corner of the bag and begin creating your spider web. Start in the center by creating a small cream cheese circle. Continue creating larger concentric circles with a little bit of gap so you can still see the pumpkin top until you run out of space (I made 5 circles). Using a toothpick inserted into the batter, start at the center circle and pull to the outside edges. Clean the toothpick each time or use a new one. Go around the entire circle repeating this pattern. Trace those lines with more cream cheese for a more pronounced spider web design.

Bake for 30-35 minutes, until wobbly-set and golden on top. Allow to cool completely before slicing.