Preheat oven to 400 degrees Fahrenheit and generously grease your cast iron skillet and line the bottom with parchment paper. Set aside.
In a medium 10-inch skillet over medium-high heat, melt the butter, stirring occasionally and letting it cook for 3-4 minutes, until dark bits begin to form and the entire butter becomes fragrant and darker. Set aside and let cool.
In a large mixing bowl, add the cornmeal, flour, baking powder, salt, pumpkin spice, and parsley, whisking them together until well combined.
Add the pumpkin puree, milk, maple syrup, and cooled brown butter, stirring everything together using a rubber spatula until well incorporated and the batter becomes thick yet easy to stir.
Scoop batter into prepared skillet and evenly spread around.
Bake for 25-30 minutes, or until the center is fully cooked through. NOTE: I usually check the middle after 25 minutes with a sharp knife to test how clean it comes out. Once fully done, the center will come out entirely clean.
Remove cornbread from oven and let it cool for 10-15 minutes before slicing and serving.