Preheat your oven to 350℉. Line an 8 inch by 8 inch square pan with parchment paper.
Brown the butter in a deep skillet over low medium heat. Cook for 5 to 7 minutes, stirring occasionally, until the butter has become a deep caramel color. Set aside in a bowl to cool.
1 Cup European Butter
In a large mixing bowl, whisk the flour, pumpkin pie spice, brown sugar, sugar, baking powder, and salt.
1 ¾ Cup Flour, 2 teaspoons Pumpkin Pie Spice, 1 Cup Light Brown Sugar, ¾ Cup Granulated Sugar, 1 teaspoon Baking Powder, ½ teaspoon Salt
Add pumpkin and egg and stir together.
1 Cup Pumpkin Purée, 1 Egg
Pour in the browned butter, scraping the bottom of the bowl to get those brown bits at the bottom!
Transfer half the batter to the parchment and bake for 8 minutes.
Meanwhile, melt the Nutella for 15 to 30 seconds in the microwave.
¾ Cup Nutella
Once the bottom layer is done baking drizzle the Nutella evenly over the whole thing and be very gentle to spread it evenly then use a spoon and scoop dollops of the remaining pumpkin batter all over the top.
Bake for an additional 25-30 min and allow to cool completely and serve.