Ingredients:

  • 2 cups (240g) all-purpose flour
  • 1 cup (200g) light brown sugar, packed
  • ½ cup (100g) granulated sugar
  • 1 tsp (5g) baking powder
  • 1 tsp (5g) baking soda
  • ½ tsp (3g) kosher salt
  • 2 tsp (5g) ground cinnamon
  • 1 tsp (2g) ground ginger
  • ½ tsp (1g) ground nutmeg
  • ¼ tsp (1g) ground cloves
  • 1 can (15 oz / 425g) pumpkin puree
  • ½ cup (115g) unsalted butter, melted and cooled
  • ½ cup (120ml) avocado oil or vegetable oil
  • 3 large eggs, room temperature
  • 1 tbsp (15ml) pure vanilla extract
  • ½ cup (65g) all-purpose flour
  • ½ cup (100g) light brown sugar, packed
  • 1 tsp (2g) ground cinnamon
  • 4 tbsp (55g) unsalted butter, cold and cubed

Instructions:

  1. Preheat oven to 350°F (175°C). Grease a 9x13 inch pan with butter or oil and line the bottom with parchment paper.
  2. In a medium bowl, whisk together the flour, baking powder, baking soda, salt, cinnamon, ginger, nutmeg, and cloves until no clumps remain.
  3. In a large bowl, beat melted butter, brown sugar, and granulated sugar until smooth. Mix in eggs one at a time, then stir in pumpkin puree, oil, and vanilla extract on medium speed until glossy.
  4. Gradually fold the dry ingredient mixture into the wet base using a spatula until just combined; do not overmix.
  5. In a small bowl, combine the topping flour, brown sugar, and cinnamon. Work in the cold, cubed butter with fingers or a fork until pea-sized clumps form.
  6. Pour batter into the prepared pan and smooth the top. Sprinkle the crumb topping evenly over the surface. Bake for 55–65 minutes until a toothpick inserted in the center comes out clean.