In a medium bowl, whisk together 1/2 cup all-purpose flour, 6 tbsp brown sugar, 1/2 tsp cinnamon, and 1/4 tsp kosher salt for the streusel. Pour in 1/4 cup melted butter and stir until just combined and crumbly. Set in the fridge to chill.

Preheat the oven to 350°F and grease a 9×5 loaf pan, then line it with parchment paper.

In a large bowl, whisk together 15 oz pumpkin puree, 3/4 cup vegetable oil, 1 cup light brown sugar, and 1/2 cup granulated sugar. Whisk in 2 large eggs one at a time.

Sprinkle 1.5 tsp baking powder, 3/4 tsp baking soda, and 3/4 tsp kosher salt over the pumpkin mixture and whisk to combine.

Repeat with 5 tsp cinnamon, 1/2 tsp freshly grated nutmeg, 1/4 tsp ground ginger, and pinch ground cloves.

Fold in 2 cups all-purpose flour until fully combined. Do not overmix.

Pour batter into the prepared pan and sprinkle the streusel over the top.

Place the pan on a baking sheet and bake for 65-80 minutes or until an inserted tester comes out clean.

Let cool in the pan for 10-15 minutes, then remove from the pan and let cool completely.