Preheat the oven at 175ºC/350ºF conventional oven and grease a 21,5 x 11,5 cm /8,5x4,5 inch loaf pan and line it with parchment paper.
In a large bowl, stir together the all-purpose flour, dark brown sugar, baking powder, baking soda, pumpkin spice and salt. Give it a stir to make sure everything has been combined.
230 g all-purpose flour, 250 g granulated sugar, 1 teaspoon baking powder, ½ teaspoon baking soda, 1 tablespoon pumpkin spice, ½ teaspoon salt
In another mixing bowl add all of the wet ingredients, and with a hand whisk, whisk them together until combined.
300 g pumpkin purée, 110 g vegetable oil, 2 large eggs, 1 teaspoon vanilla extract
Pour the wet ingredients into the dry and stir it together until smooth and combined.
Then pour the cake batter into the prepared loaf pan. Take a butter knife and insert it into the top of the batter in the loaf pan and run it a straight line down the middle of the batter.
Top the pumpkin bread with the streusel and bake it for 65-75 minutes or until a cake tester comes out clean. Once baked, let the cake cool on a cooling rack. After 10 minutes, gently remove the cake from the loaf pan and let it cool down completely.