• Preheat the oven to 325°F (160°C) or 300°F (150°C fan) about 8–10 minutes before you put the cake in the oven.
• Line a 9×5-inch (23×13 cm) loaf pan with parchment paper.
• Dry ingredients: In a bowl, whisk together the flour, baking powder, baking soda, pumpkin spice (or cinnamon), and salt.
• Pumpkin mixture: In another bowl, whisk pumpkin purée, eggs, sugar, oil, milk, yogurt (if using) and vanilla extract until smooth.
• Combine: Add the dry ingredients to the pumpkin mixture and fold gently until smooth. Do not overmix.
• Make the chocolate batter: Scoop out about 1 cup (260 g) of pumpkin batter into a separate bowl. Add cocoa powder and milk, then whisk until smooth.

Layering chocolate and pumpkin batter

• Spread a layer of pumpkin batter into the loaf pan, then add a layer of chocolate batter.
• Keep alternating until both batters are finished, making sure to start and finish with pumpkin.

  You don’t need to smooth each layer; the batter settles naturally. I did 4 layers of pumpkin and 3 of chocolate.
• Optional topping: If not using frosting, sprinkle about 1 Tablespoon pumpkin spice sugar before baking and another Tablespoon after baking for a light, crisp crust.
• Bake for 55–60 minutes, or until a toothpick inserted in the center comes out clean or with a few sticky crumbs (not wet batter).
• If the top browns too quickly: Cover loosely with foil during baking so it doesn’t touch the batter.
• Cool in the pan for 10–15 minutes, then transfer to a wire rack to cool completely before slicing.

Storage

• Room temperature: Store cooled cake in an airtight container for up to 3 days.
• Refrigerate: Keeps up to 5 days; bring to room temperature before serving.
• Freeze: Wrap slices or the whole loaf tightly and freeze for up to 2 months. Thaw at room temperature before serving.

Watch the short video in the post to see how it’s made.