1. Preheat the oven to 180°C (350°F). Line a loaf tin* (about 23x13cm) with a piece of baking parchment and grease lightly. Set aside. Melt the butter and let cool down.

2. In a large bowl, mix melted butter and both sugars until light and fluffy. Add the pumpkin purée, the 120ml of milk, eggs, and vanilla extract – mix until well combined. In a separate bowl mix flour, pumpkin pie spice, baking powder, baking soda, and salt. Add these dry ingredients to the large bowl and fold in with a rubber spatula. Take about 1/3 of the batter out into a separate bowl, add the cocoa powder and the 3 tablespoons of milk and mix until well combined.

3. Layer the two batters, starting with the light batter. Depending on the thickness of your batter, you might have to spread each batter with an offset spatula to create even layers. If your batter is runny enough, it will do that pretty much on its own. Finish with light batter, smooth out the top and bake the cake for about 70-80 minutes or until a wooden skewer inserted into the center of the cake comes out clean. Take the cake out of the oven and let cool down inside the baking tin for about 10-15 minutes, then lift the cake out of the tin with the baking parchment and let cool down completely on a wire rack.