Preheat your oven to 350°F (175°C) and grease a 9x13-inch baking pan.

Combine flour, brown sugar, granulated sugar, salt, cinnamon, and pumpkin pie spice for the streusel topping.

In a separate bowl, whisk together the dry ingredients.

In a mixing bowl, blend softened butter and half of the pumpkin puree until crumbly.

In another bowl, combine remaining pumpkin puree, eggs, vegetable oil, and vanilla extract, whisking until smooth.

Gradually add the wet ingredients into the dry mixture and mix until just combined.

Layer half of the batter and half of the streusel topping in the prepared pan, then top with remaining batter and streusel.

Bake for 35-45 minutes, checking for doneness with a toothpick.

Cool for 15-20 minutes, then prepare the glaze and drizzle over the cake.