- Preheat oven to 350ºF and line a 13×9 baking pan with parchment paper. Combine panko bread crumbs, melted butter, brown sugar, ¼ cup flour, and 1 egg in a medium mixing bowl. Stir until well moistened. Press mixture into the bottom of baking pan. Bake 10 minutes. Cool crust 10 minutes at room temperature.
- Reduce oven temperature to 325ºF. While the crust cools, combine all cream cheese, sour cream, cane sugar, 2 eggs, 1 tablespoon flour, and vanilla in a medium mixing bowl. Use a hand mixer on medium speed to thoroughly combine ingredients until smooth. Set aside.
- In a separate mixing bowl, combine pumpkin purée, pumpkin spice, and ½ cup of the cream cheese mixture.
- Spread remaining cream cheese mixture evenly over crust using a spatula. Spoon dollops of pumpkin topping on top of cream cheese layer and use a sharp knife to create a marble effect by dragging through cream cheese layer, avoiding the crust. Bake 45 minutes. Cool on a wire rack for 1 hour then transfer to refrigerator for 2 hours before slicing into bars.