Ingredients
Equipment
Method
Prep the loaf pan
- Preheat the oven to 350°F (175°C). Grease and line a 9×5-inch loaf pan with parchment paper.
Make the pumpkin batter
- Whisk together the all-purpose flour, baking soda, baking powder, pumpkin pie spice, ground cinnamon, and salt in a medium bowl.
- In a large bowl, whisk together the eggs, granulated sugar, and light brown sugar until smooth.
- Add the pumpkin purée, vegetable oil, sour cream, and vanilla extract, then mix until fully combined.
- Gradually fold the dry ingredients into the wet ingredients until just combined, keeping the batter thick and not overmixed.
Build the cinnamon swirl
- Mix the light brown sugar, ground cinnamon, and melted unsalted butter for the swirl until evenly combined.
- Spread half of the batter into the prepared loaf pan, sprinkle with half the cinnamon mixture, then add remaining batter and the rest of the cinnamon mixture.
- Use a butter knife to gently swirl the cinnamon filling through the batter so streaks form throughout.
Bake and glaze
- Bake at 350°F (175°C) for 55–65 minutes, until a toothpick in the center comes out clean or with a few moist crumbs.
- Cool the loaf in the pan for 15 minutes, then transfer it to a wire rack to cool completely.
- Whisk powdered sugar, heavy cream, and vanilla extract until smooth, then drizzle generously over the cooled loaf.
Notes
For the tightest swirl, stop mixing once the dry ingredients disappear—lumps are fine, overmixing can dull the ribbon texture. Store the loaf airtight in the fridge up to 4 days; freeze sliced portions up to 2 months and thaw overnight in the fridge. For a lighter option, substitute Greek yogurt for the sour cream in equal amount to keep the crumb moist.
