In a small bowl, combine the flour, brown sugar, cinnamon, and salt. Add in the cold butter and cut it in with a pastry cutter or a fork until you have a crumb mixture. Place the bowl in the freezer until needed.

Preheat the oven to 350ºF. Line a 9x9-inch pan with parchment paper or spray with nonstick cooking spray.

In a large bowl, combine the flour, baking soda, baking powder, salt, cinnamon, and pumpkin pie spice. Whisk to combine.

In another bowl, combine the pumpkin puree, brown sugar, vegetable oil, sugar, buttermilk and egg. Whisk until smooth.

Pour the wet ingredients into the dry ingredients and stir just until combined.

Pour the batter into the prepared baking pan. Take the crumb mixture and sprinkle it evenly over the top.

Bake the cake until a tester inserted in the middle comes out clean, about 36-40 minutes.

When the cake is almost done, make the glaze by whisking together the powdered sugar, milk, cinnamon, maple extract, and pinch of salt.

Once the cake is finished, remove it from the oven. Drizzle the glaze over the top, then allow the cake to cool.