In a small bowl, combine all-purpose flour, brown sugar, pumpkin seeds, and pumpkin pie spice. Drizzle in melted unsalted butter, mixing until you have coarse crumbs. Refrigerate for at least 15 minutes.

Preheat your oven to 325°F (163°C) and grease a 10x5 inch loaf pan with butter or non-stick spray. Line with parchment for easier removal.

In a medium mixing bowl, whisk together the all-purpose flour, baking soda, baking powder, and salt. Set aside.

In a large mixing bowl, whisk together the pure pumpkin puree, granulated sugar, pure maple syrup, eggs, vanilla extract, cinnamon, and pumpkin pie spice until smooth. Gradually add melted butter and neutral oil until well incorporated.

Fold half of the flour mixture into the pumpkin batter, then add whole milk. Once incorporated, fold in remaining flour mixture until just combined.

Pour the batter into the prepared loaf pan. Retrieve chilled streusel and break into clusters, then evenly distribute over the batter.

Bake for 1 hour and 15 minutes, rotating midway. Check for doneness with a toothpick; it should come out clean or with a few moist crumbs. Add 5 more minutes if needed.

Cool in the pan for 20 minutes, lift using parchment overhang, and transfer to a wire rack to cool completely. Slice and serve warm or store for later enjoyment.